From 0e8e2238b52e5301d1d1d4a298ec5b72ac54c702 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:09 -0600 Subject: [PATCH 01/52] x86/xen: Add stack frame dependency to hypercall inline asm calls If a hypercall is inlined at the beginning of a function, gcc can insert the call instruction before setting up a stack frame, which breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and can result in a bad stack trace. Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by listing the stack pointer as an output operand for the hypercall inline asm statements. Signed-off-by: Josh Poimboeuf Reviewed-by: David Vrabel Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Konrad Rzeszutek Wilk Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/c6face5a46713108bded9c4c103637222abc4528.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/xen/hypercall.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h index 3bcdcc84259d..a12a047184ee 100644 --- a/arch/x86/include/asm/xen/hypercall.h +++ b/arch/x86/include/asm/xen/hypercall.h @@ -110,9 +110,10 @@ extern struct { char _entry[32]; } hypercall_page[]; register unsigned long __arg2 asm(__HYPERCALL_ARG2REG) = __arg2; \ register unsigned long __arg3 asm(__HYPERCALL_ARG3REG) = __arg3; \ register unsigned long __arg4 asm(__HYPERCALL_ARG4REG) = __arg4; \ - register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5; + register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5; \ + register void *__sp asm(_ASM_SP); -#define __HYPERCALL_0PARAM "=r" (__res) +#define __HYPERCALL_0PARAM "=r" (__res), "+r" (__sp) #define __HYPERCALL_1PARAM __HYPERCALL_0PARAM, "+r" (__arg1) #define __HYPERCALL_2PARAM __HYPERCALL_1PARAM, "+r" (__arg2) #define __HYPERCALL_3PARAM __HYPERCALL_2PARAM, "+r" (__arg3) From 9fd216067d75b45eb18d84dc476059de47da07c2 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:10 -0600 Subject: [PATCH 02/52] x86/asm/xen: Set ELF function type for xen_adjust_exception_frame() xen_adjust_exception_frame() is a callable function, but is missing the ELF function type, which confuses tools like stacktool. Properly annotate it to be a callable function. The generated code is unchanged. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: David Vrabel Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Konrad Rzeszutek Wilk Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/b1851bd17a0986472692a7e3a05290d891382cdd.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/xen/xen-asm_64.S | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S index cc8acc410ddb..c3df43141e70 100644 --- a/arch/x86/xen/xen-asm_64.S +++ b/arch/x86/xen/xen-asm_64.S @@ -26,6 +26,7 @@ ENTRY(xen_adjust_exception_frame) mov 8+0(%rsp), %rcx mov 8+8(%rsp), %r11 ret $16 +ENDPROC(xen_adjust_exception_frame) hypercall_iret = hypercall_page + __HYPERVISOR_iret * 32 /* From 8be0eb7e0d53bc2dbe6e9ad6e96a2d5b89d148a8 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:11 -0600 Subject: [PATCH 03/52] x86/asm/xen: Create stack frames in xen-asm.S xen_irq_enable_direct(), xen_restore_fl_direct(), and check_events() are callable non-leaf functions which don't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create stack frames for them when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: David Vrabel Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Konrad Rzeszutek Wilk Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/a8340ad3fc72ba9ed34da9b3af9cdd6f1a896e17.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/xen/xen-asm.S | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S index 3e45aa000718..eff224df813f 100644 --- a/arch/x86/xen/xen-asm.S +++ b/arch/x86/xen/xen-asm.S @@ -14,6 +14,7 @@ #include #include #include +#include #include "xen-asm.h" @@ -23,6 +24,7 @@ * then enter the hypervisor to get them handled. */ ENTRY(xen_irq_enable_direct) + FRAME_BEGIN /* Unmask events */ movb $0, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask @@ -39,6 +41,7 @@ ENTRY(xen_irq_enable_direct) 2: call check_events 1: ENDPATCH(xen_irq_enable_direct) + FRAME_END ret ENDPROC(xen_irq_enable_direct) RELOC(xen_irq_enable_direct, 2b+1) @@ -82,6 +85,7 @@ ENDPATCH(xen_save_fl_direct) * enters the hypervisor to get them delivered if so. */ ENTRY(xen_restore_fl_direct) + FRAME_BEGIN #ifdef CONFIG_X86_64 testw $X86_EFLAGS_IF, %di #else @@ -100,6 +104,7 @@ ENTRY(xen_restore_fl_direct) 2: call check_events 1: ENDPATCH(xen_restore_fl_direct) + FRAME_END ret ENDPROC(xen_restore_fl_direct) RELOC(xen_restore_fl_direct, 2b+1) @@ -109,7 +114,8 @@ ENDPATCH(xen_restore_fl_direct) * Force an event check by making a hypercall, but preserve regs * before making the call. */ -check_events: +ENTRY(check_events) + FRAME_BEGIN #ifdef CONFIG_X86_32 push %eax push %ecx @@ -139,4 +145,6 @@ check_events: pop %rcx pop %rax #endif + FRAME_END ret +ENDPROC(check_events) From bb93eb4cd606888f879897e8289d9c1143571feb Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:12 -0600 Subject: [PATCH 04/52] x86/paravirt: Add stack frame dependency to PVOP inline asm calls If a PVOP call macro is inlined at the beginning of a function, gcc can insert the call instruction before setting up a stack frame, which breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and can result in a bad stack trace. Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by listing the stack pointer as an output operand for the PVOP inline asm statements. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Cc: Alok Kataria Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Chris Wright Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jeremy Fitzhardinge Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Rusty Russell Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/6a13e48c5a8cf2de1aa112ae2d4c0ac194096282.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/paravirt_types.h | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 77db5616a473..e8c2326478c8 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -466,8 +466,9 @@ int paravirt_disable_iospace(void); * makes sure the incoming and outgoing types are always correct. */ #ifdef CONFIG_X86_32 -#define PVOP_VCALL_ARGS \ - unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx +#define PVOP_VCALL_ARGS \ + unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx; \ + register void *__sp asm("esp") #define PVOP_CALL_ARGS PVOP_VCALL_ARGS #define PVOP_CALL_ARG1(x) "a" ((unsigned long)(x)) @@ -485,9 +486,10 @@ int paravirt_disable_iospace(void); #define VEXTRA_CLOBBERS #else /* CONFIG_X86_64 */ /* [re]ax isn't an arg, but the return val */ -#define PVOP_VCALL_ARGS \ - unsigned long __edi = __edi, __esi = __esi, \ - __edx = __edx, __ecx = __ecx, __eax = __eax +#define PVOP_VCALL_ARGS \ + unsigned long __edi = __edi, __esi = __esi, \ + __edx = __edx, __ecx = __ecx, __eax = __eax; \ + register void *__sp asm("rsp") #define PVOP_CALL_ARGS PVOP_VCALL_ARGS #define PVOP_CALL_ARG1(x) "D" ((unsigned long)(x)) @@ -526,7 +528,7 @@ int paravirt_disable_iospace(void); asm volatile(pre \ paravirt_alt(PARAVIRT_CALL) \ post \ - : call_clbr \ + : call_clbr, "+r" (__sp) \ : paravirt_type(op), \ paravirt_clobber(clbr), \ ##__VA_ARGS__ \ @@ -536,7 +538,7 @@ int paravirt_disable_iospace(void); asm volatile(pre \ paravirt_alt(PARAVIRT_CALL) \ post \ - : call_clbr \ + : call_clbr, "+r" (__sp) \ : paravirt_type(op), \ paravirt_clobber(clbr), \ ##__VA_ARGS__ \ @@ -563,7 +565,7 @@ int paravirt_disable_iospace(void); asm volatile(pre \ paravirt_alt(PARAVIRT_CALL) \ post \ - : call_clbr \ + : call_clbr, "+r" (__sp) \ : paravirt_type(op), \ paravirt_clobber(clbr), \ ##__VA_ARGS__ \ From 87b240cbe3e51bf070fe2839fecb6450323aaef4 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:13 -0600 Subject: [PATCH 05/52] x86/paravirt: Create a stack frame in PV_CALLEE_SAVE_REGS_THUNK A function created with the PV_CALLEE_SAVE_REGS_THUNK macro doesn't set up a new stack frame before the call instruction, which breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and can result in a bad stack trace. Also, the thunk functions aren't annotated as ELF callable functions. Create a stack frame when CONFIG_FRAME_POINTER is enabled and add the ELF function type. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Cc: Alok Kataria Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Chris Wright Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jeremy Fitzhardinge Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Rusty Russell Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/a2cad74e87c4aba7fd0f54a1af312e66a824a575.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/paravirt.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index f6192502149e..601f1b8f9961 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -13,6 +13,7 @@ #include #include #include +#include static inline int paravirt_enabled(void) { @@ -756,15 +757,19 @@ static __always_inline void __ticket_unlock_kick(struct arch_spinlock *lock, * call. The return value in rax/eax will not be saved, even for void * functions. */ +#define PV_THUNK_NAME(func) "__raw_callee_save_" #func #define PV_CALLEE_SAVE_REGS_THUNK(func) \ extern typeof(func) __raw_callee_save_##func; \ \ asm(".pushsection .text;" \ - ".globl __raw_callee_save_" #func " ; " \ - "__raw_callee_save_" #func ": " \ + ".globl " PV_THUNK_NAME(func) ";" \ + ".type " PV_THUNK_NAME(func) ", @function;" \ + PV_THUNK_NAME(func) ":" \ + FRAME_BEGIN \ PV_SAVE_ALL_CALLER_REGS \ "call " #func ";" \ PV_RESTORE_ALL_CALLER_REGS \ + FRAME_END \ "ret;" \ ".popsection") From de642faf48670c3c8eae5899177f786c624f4894 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:14 -0600 Subject: [PATCH 06/52] x86/amd: Set ELF function type for vide() vide() is a callable function, but is missing the ELF function type, which confuses tools like stacktool. Properly annotate it to be a callable function. The generated code is unchanged. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/a324095f5c9390ff39b15b4562ea1bbeda1a8282.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/amd.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index a07956a08936..fe2f089f03d2 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -75,7 +75,10 @@ static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val) */ extern __visible void vide(void); -__asm__(".globl vide\n\t.align 4\nvide: ret"); +__asm__(".globl vide\n" + ".type vide, @function\n" + ".align 4\n" + "vide: ret\n"); static void init_amd_k5(struct cpuinfo_x86 *c) { From 1253cab8a35278c0493a48aa5ab74992f7a849ea Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:15 -0600 Subject: [PATCH 07/52] x86/asm/crypto: Move .Lbswap_mask data to .rodata section stacktool reports the following warning: stacktool: arch/x86/crypto/aesni-intel_asm.o: _aesni_inc_init(): can't find starting instruction stacktool gets confused when it tries to disassemble the following data in the .text section: .Lbswap_mask: .byte 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 Move it to .rodata which is a more appropriate section for read-only data. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: David S. Miller Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Herbert Xu Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/b6a2f3f8bda705143e127c025edb2b53c86e6eb4.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/crypto/aesni-intel_asm.S | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S index 6bd2c6c95373..c44cfedbe1c3 100644 --- a/arch/x86/crypto/aesni-intel_asm.S +++ b/arch/x86/crypto/aesni-intel_asm.S @@ -2538,9 +2538,11 @@ ENTRY(aesni_cbc_dec) ENDPROC(aesni_cbc_dec) #ifdef __x86_64__ +.pushsection .rodata .align 16 .Lbswap_mask: .byte 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 +.popsection /* * _aesni_inc_init: internal ABI From f66f61919eb38c5f20e8a978cae7ecdede4c23b9 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:16 -0600 Subject: [PATCH 08/52] x86/asm/crypto: Move jump_table to .rodata section stacktool reports the following warning: stacktool: arch/x86/crypto/crc32c-pcl-intel-asm_64.o: crc_pcl()+0x11dd: can't decode instruction It gets confused when trying to decode jump_table data. Move jump_table to the .rodata section which is a more appropriate home for read-only data. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: David S. Miller Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Herbert Xu Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/1dbf80c097bb9d89c0cbddc01a815ada690e3b32.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/crypto/crc32c-pcl-intel-asm_64.S | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/crypto/crc32c-pcl-intel-asm_64.S b/arch/x86/crypto/crc32c-pcl-intel-asm_64.S index 4fe27e074194..dc05f010ca9b 100644 --- a/arch/x86/crypto/crc32c-pcl-intel-asm_64.S +++ b/arch/x86/crypto/crc32c-pcl-intel-asm_64.S @@ -170,8 +170,8 @@ continue_block: ## branch into array lea jump_table(%rip), bufp movzxw (bufp, %rax, 2), len - offset=crc_array-jump_table - lea offset(bufp, len, 1), bufp + lea crc_array(%rip), bufp + lea (bufp, len, 1), bufp jmp *bufp ################################################################ @@ -310,7 +310,9 @@ do_return: popq %rdi popq %rbx ret +ENDPROC(crc_pcl) +.section .rodata, "a", %progbits ################################################################ ## jump table Table is 129 entries x 2 bytes each ################################################################ @@ -324,13 +326,11 @@ JMPTBL_ENTRY %i i=i+1 .endr -ENDPROC(crc_pcl) ################################################################ ## PCLMULQDQ tables ## Table is 128 entries x 2 words (8 bytes) each ################################################################ -.section .rodata, "a", %progbits .align 8 K_table: .long 0x493c7d27, 0x00000001 From aec4d0e301f17bb143341c82cc44685b8af0b945 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:17 -0600 Subject: [PATCH 09/52] x86/asm/crypto: Simplify stack usage in sha-mb functions sha1_mb_mgr_flush_avx2() and sha1_mb_mgr_submit_avx2() both allocate a lot of stack space which is never used. Also, many of the registers being saved aren't being clobbered so there's no need to save them. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/9402e4d87580d6b2376ed95f67b84bdcce3c830e.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- .../crypto/sha-mb/sha1_mb_mgr_flush_avx2.S | 32 ++----------------- .../crypto/sha-mb/sha1_mb_mgr_submit_avx2.S | 29 +++-------------- 2 files changed, 6 insertions(+), 55 deletions(-) diff --git a/arch/x86/crypto/sha-mb/sha1_mb_mgr_flush_avx2.S b/arch/x86/crypto/sha-mb/sha1_mb_mgr_flush_avx2.S index 85c4e1cf7172..672eaeb258a5 100644 --- a/arch/x86/crypto/sha-mb/sha1_mb_mgr_flush_avx2.S +++ b/arch/x86/crypto/sha-mb/sha1_mb_mgr_flush_avx2.S @@ -86,16 +86,6 @@ #define extra_blocks %arg2 #define p %arg2 - -# STACK_SPACE needs to be an odd multiple of 8 -_XMM_SAVE_SIZE = 10*16 -_GPR_SAVE_SIZE = 8*8 -_ALIGN_SIZE = 8 - -_XMM_SAVE = 0 -_GPR_SAVE = _XMM_SAVE + _XMM_SAVE_SIZE -STACK_SPACE = _GPR_SAVE + _GPR_SAVE_SIZE + _ALIGN_SIZE - .macro LABEL prefix n \prefix\n\(): .endm @@ -113,16 +103,7 @@ offset = \_offset # JOB* sha1_mb_mgr_flush_avx2(MB_MGR *state) # arg 1 : rcx : state ENTRY(sha1_mb_mgr_flush_avx2) - mov %rsp, %r10 - sub $STACK_SPACE, %rsp - and $~31, %rsp - mov %rbx, _GPR_SAVE(%rsp) - mov %r10, _GPR_SAVE+8*1(%rsp) #save rsp - mov %rbp, _GPR_SAVE+8*3(%rsp) - mov %r12, _GPR_SAVE+8*4(%rsp) - mov %r13, _GPR_SAVE+8*5(%rsp) - mov %r14, _GPR_SAVE+8*6(%rsp) - mov %r15, _GPR_SAVE+8*7(%rsp) + push %rbx # If bit (32+3) is set, then all lanes are empty mov _unused_lanes(state), unused_lanes @@ -230,16 +211,7 @@ len_is_0: mov tmp2_w, offset(job_rax) return: - - mov _GPR_SAVE(%rsp), %rbx - mov _GPR_SAVE+8*1(%rsp), %r10 #saved rsp - mov _GPR_SAVE+8*3(%rsp), %rbp - mov _GPR_SAVE+8*4(%rsp), %r12 - mov _GPR_SAVE+8*5(%rsp), %r13 - mov _GPR_SAVE+8*6(%rsp), %r14 - mov _GPR_SAVE+8*7(%rsp), %r15 - mov %r10, %rsp - + pop %rbx ret return_null: diff --git a/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S b/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S index 2ab9560b53c8..a5a14c62d843 100644 --- a/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S +++ b/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S @@ -94,25 +94,12 @@ DWORD_tmp = %r9d lane_data = %r10 -# STACK_SPACE needs to be an odd multiple of 8 -STACK_SPACE = 8*8 + 16*10 + 8 - # JOB* submit_mb_mgr_submit_avx2(MB_MGR *state, job_sha1 *job) # arg 1 : rcx : state # arg 2 : rdx : job ENTRY(sha1_mb_mgr_submit_avx2) - - mov %rsp, %r10 - sub $STACK_SPACE, %rsp - and $~31, %rsp - - mov %rbx, (%rsp) - mov %r10, 8*2(%rsp) #save old rsp - mov %rbp, 8*3(%rsp) - mov %r12, 8*4(%rsp) - mov %r13, 8*5(%rsp) - mov %r14, 8*6(%rsp) - mov %r15, 8*7(%rsp) + push %rbx + push %rbp mov _unused_lanes(state), unused_lanes mov unused_lanes, lane @@ -203,16 +190,8 @@ len_is_0: movl DWORD_tmp, _result_digest+1*16(job_rax) return: - - mov (%rsp), %rbx - mov 8*2(%rsp), %r10 #save old rsp - mov 8*3(%rsp), %rbp - mov 8*4(%rsp), %r12 - mov 8*5(%rsp), %r13 - mov 8*6(%rsp), %r14 - mov 8*7(%rsp), %r15 - mov %r10, %rsp - + pop %rbp + pop %rbx ret return_null: From 68874ac3304ade7ed5ebb12af00d6b9bbbca0a16 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:18 -0600 Subject: [PATCH 10/52] x86/asm/crypto: Don't use RBP as a scratch register The frame pointer (RBP) is getting clobbered in sha1_mb_mgr_submit_avx2() before a function call, which can mess up stack traces. Use R12 instead. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/15a3eb7ebe68e37755927915f45e4f0bde4d18c5.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S b/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S index a5a14c62d843..c3b944781d3f 100644 --- a/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S +++ b/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S @@ -86,8 +86,8 @@ job_rax = %rax len = %rax DWORD_len = %eax -lane = %rbp -tmp3 = %rbp +lane = %r12 +tmp3 = %r12 tmp = %r9 DWORD_tmp = %r9d @@ -99,7 +99,7 @@ lane_data = %r10 # arg 2 : rdx : job ENTRY(sha1_mb_mgr_submit_avx2) push %rbx - push %rbp + push %r12 mov _unused_lanes(state), unused_lanes mov unused_lanes, lane @@ -190,7 +190,7 @@ len_is_0: movl DWORD_tmp, _result_digest+1*16(job_rax) return: - pop %rbp + pop %r12 pop %rbx ret From 8691ccd764f9ecc69a6812dfe76214c86ac9ba06 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:19 -0600 Subject: [PATCH 11/52] x86/asm/crypto: Create stack frames in crypto functions The crypto code has several callable non-leaf functions which don't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create stack frames for them when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: David S. Miller Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Herbert Xu Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/6c20192bcf1102ae18ae5a242cabf30ce9b29895.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/crypto/aesni-intel_asm.S | 73 ++++++++++++------- arch/x86/crypto/camellia-aesni-avx-asm_64.S | 15 ++++ arch/x86/crypto/camellia-aesni-avx2-asm_64.S | 15 ++++ arch/x86/crypto/cast5-avx-x86_64-asm_64.S | 9 +++ arch/x86/crypto/cast6-avx-x86_64-asm_64.S | 13 ++++ arch/x86/crypto/ghash-clmulni-intel_asm.S | 5 ++ arch/x86/crypto/serpent-avx-x86_64-asm_64.S | 13 ++++ arch/x86/crypto/serpent-avx2-asm_64.S | 13 ++++ .../crypto/sha-mb/sha1_mb_mgr_flush_avx2.S | 3 + .../crypto/sha-mb/sha1_mb_mgr_submit_avx2.S | 3 + arch/x86/crypto/twofish-avx-x86_64-asm_64.S | 13 ++++ 11 files changed, 148 insertions(+), 27 deletions(-) diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S index c44cfedbe1c3..383a6f84a060 100644 --- a/arch/x86/crypto/aesni-intel_asm.S +++ b/arch/x86/crypto/aesni-intel_asm.S @@ -31,6 +31,7 @@ #include #include +#include /* * The following macros are used to move an (un)aligned 16 byte value to/from @@ -1800,11 +1801,12 @@ ENDPROC(_key_expansion_256b) * unsigned int key_len) */ ENTRY(aesni_set_key) + FRAME_BEGIN #ifndef __x86_64__ pushl KEYP - movl 8(%esp), KEYP # ctx - movl 12(%esp), UKEYP # in_key - movl 16(%esp), %edx # key_len + movl (FRAME_OFFSET+8)(%esp), KEYP # ctx + movl (FRAME_OFFSET+12)(%esp), UKEYP # in_key + movl (FRAME_OFFSET+16)(%esp), %edx # key_len #endif movups (UKEYP), %xmm0 # user key (first 16 bytes) movaps %xmm0, (KEYP) @@ -1905,6 +1907,7 @@ ENTRY(aesni_set_key) #ifndef __x86_64__ popl KEYP #endif + FRAME_END ret ENDPROC(aesni_set_key) @@ -1912,12 +1915,13 @@ ENDPROC(aesni_set_key) * void aesni_enc(struct crypto_aes_ctx *ctx, u8 *dst, const u8 *src) */ ENTRY(aesni_enc) + FRAME_BEGIN #ifndef __x86_64__ pushl KEYP pushl KLEN - movl 12(%esp), KEYP - movl 16(%esp), OUTP - movl 20(%esp), INP + movl (FRAME_OFFSET+12)(%esp), KEYP # ctx + movl (FRAME_OFFSET+16)(%esp), OUTP # dst + movl (FRAME_OFFSET+20)(%esp), INP # src #endif movl 480(KEYP), KLEN # key length movups (INP), STATE # input @@ -1927,6 +1931,7 @@ ENTRY(aesni_enc) popl KLEN popl KEYP #endif + FRAME_END ret ENDPROC(aesni_enc) @@ -2101,12 +2106,13 @@ ENDPROC(_aesni_enc4) * void aesni_dec (struct crypto_aes_ctx *ctx, u8 *dst, const u8 *src) */ ENTRY(aesni_dec) + FRAME_BEGIN #ifndef __x86_64__ pushl KEYP pushl KLEN - movl 12(%esp), KEYP - movl 16(%esp), OUTP - movl 20(%esp), INP + movl (FRAME_OFFSET+12)(%esp), KEYP # ctx + movl (FRAME_OFFSET+16)(%esp), OUTP # dst + movl (FRAME_OFFSET+20)(%esp), INP # src #endif mov 480(KEYP), KLEN # key length add $240, KEYP @@ -2117,6 +2123,7 @@ ENTRY(aesni_dec) popl KLEN popl KEYP #endif + FRAME_END ret ENDPROC(aesni_dec) @@ -2292,14 +2299,15 @@ ENDPROC(_aesni_dec4) * size_t len) */ ENTRY(aesni_ecb_enc) + FRAME_BEGIN #ifndef __x86_64__ pushl LEN pushl KEYP pushl KLEN - movl 16(%esp), KEYP - movl 20(%esp), OUTP - movl 24(%esp), INP - movl 28(%esp), LEN + movl (FRAME_OFFSET+16)(%esp), KEYP # ctx + movl (FRAME_OFFSET+20)(%esp), OUTP # dst + movl (FRAME_OFFSET+24)(%esp), INP # src + movl (FRAME_OFFSET+28)(%esp), LEN # len #endif test LEN, LEN # check length jz .Lecb_enc_ret @@ -2342,6 +2350,7 @@ ENTRY(aesni_ecb_enc) popl KEYP popl LEN #endif + FRAME_END ret ENDPROC(aesni_ecb_enc) @@ -2350,14 +2359,15 @@ ENDPROC(aesni_ecb_enc) * size_t len); */ ENTRY(aesni_ecb_dec) + FRAME_BEGIN #ifndef __x86_64__ pushl LEN pushl KEYP pushl KLEN - movl 16(%esp), KEYP - movl 20(%esp), OUTP - movl 24(%esp), INP - movl 28(%esp), LEN + movl (FRAME_OFFSET+16)(%esp), KEYP # ctx + movl (FRAME_OFFSET+20)(%esp), OUTP # dst + movl (FRAME_OFFSET+24)(%esp), INP # src + movl (FRAME_OFFSET+28)(%esp), LEN # len #endif test LEN, LEN jz .Lecb_dec_ret @@ -2401,6 +2411,7 @@ ENTRY(aesni_ecb_dec) popl KEYP popl LEN #endif + FRAME_END ret ENDPROC(aesni_ecb_dec) @@ -2409,16 +2420,17 @@ ENDPROC(aesni_ecb_dec) * size_t len, u8 *iv) */ ENTRY(aesni_cbc_enc) + FRAME_BEGIN #ifndef __x86_64__ pushl IVP pushl LEN pushl KEYP pushl KLEN - movl 20(%esp), KEYP - movl 24(%esp), OUTP - movl 28(%esp), INP - movl 32(%esp), LEN - movl 36(%esp), IVP + movl (FRAME_OFFSET+20)(%esp), KEYP # ctx + movl (FRAME_OFFSET+24)(%esp), OUTP # dst + movl (FRAME_OFFSET+28)(%esp), INP # src + movl (FRAME_OFFSET+32)(%esp), LEN # len + movl (FRAME_OFFSET+36)(%esp), IVP # iv #endif cmp $16, LEN jb .Lcbc_enc_ret @@ -2443,6 +2455,7 @@ ENTRY(aesni_cbc_enc) popl LEN popl IVP #endif + FRAME_END ret ENDPROC(aesni_cbc_enc) @@ -2451,16 +2464,17 @@ ENDPROC(aesni_cbc_enc) * size_t len, u8 *iv) */ ENTRY(aesni_cbc_dec) + FRAME_BEGIN #ifndef __x86_64__ pushl IVP pushl LEN pushl KEYP pushl KLEN - movl 20(%esp), KEYP - movl 24(%esp), OUTP - movl 28(%esp), INP - movl 32(%esp), LEN - movl 36(%esp), IVP + movl (FRAME_OFFSET+20)(%esp), KEYP # ctx + movl (FRAME_OFFSET+24)(%esp), OUTP # dst + movl (FRAME_OFFSET+28)(%esp), INP # src + movl (FRAME_OFFSET+32)(%esp), LEN # len + movl (FRAME_OFFSET+36)(%esp), IVP # iv #endif cmp $16, LEN jb .Lcbc_dec_just_ret @@ -2534,6 +2548,7 @@ ENTRY(aesni_cbc_dec) popl LEN popl IVP #endif + FRAME_END ret ENDPROC(aesni_cbc_dec) @@ -2600,6 +2615,7 @@ ENDPROC(_aesni_inc) * size_t len, u8 *iv) */ ENTRY(aesni_ctr_enc) + FRAME_BEGIN cmp $16, LEN jb .Lctr_enc_just_ret mov 480(KEYP), KLEN @@ -2653,6 +2669,7 @@ ENTRY(aesni_ctr_enc) .Lctr_enc_ret: movups IV, (IVP) .Lctr_enc_just_ret: + FRAME_END ret ENDPROC(aesni_ctr_enc) @@ -2679,6 +2696,7 @@ ENDPROC(aesni_ctr_enc) * bool enc, u8 *iv) */ ENTRY(aesni_xts_crypt8) + FRAME_BEGIN cmpb $0, %cl movl $0, %ecx movl $240, %r10d @@ -2779,6 +2797,7 @@ ENTRY(aesni_xts_crypt8) pxor INC, STATE4 movdqu STATE4, 0x70(OUTP) + FRAME_END ret ENDPROC(aesni_xts_crypt8) diff --git a/arch/x86/crypto/camellia-aesni-avx-asm_64.S b/arch/x86/crypto/camellia-aesni-avx-asm_64.S index ce71f9212409..aa9e8bd163f6 100644 --- a/arch/x86/crypto/camellia-aesni-avx-asm_64.S +++ b/arch/x86/crypto/camellia-aesni-avx-asm_64.S @@ -16,6 +16,7 @@ */ #include +#include #define CAMELLIA_TABLE_BYTE_LEN 272 @@ -726,6 +727,7 @@ __camellia_enc_blk16: * %xmm0..%xmm15: 16 encrypted blocks, order swapped: * 7, 8, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8 */ + FRAME_BEGIN leaq 8 * 16(%rax), %rcx; @@ -780,6 +782,7 @@ __camellia_enc_blk16: %xmm8, %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, %xmm14, %xmm15, (key_table)(CTX, %r8, 8), (%rax), 1 * 16(%rax)); + FRAME_END ret; .align 8 @@ -812,6 +815,7 @@ __camellia_dec_blk16: * %xmm0..%xmm15: 16 plaintext blocks, order swapped: * 7, 8, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8 */ + FRAME_BEGIN leaq 8 * 16(%rax), %rcx; @@ -865,6 +869,7 @@ __camellia_dec_blk16: %xmm8, %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, %xmm14, %xmm15, (key_table)(CTX), (%rax), 1 * 16(%rax)); + FRAME_END ret; .align 8 @@ -890,6 +895,7 @@ ENTRY(camellia_ecb_enc_16way) * %rsi: dst (16 blocks) * %rdx: src (16 blocks) */ + FRAME_BEGIN inpack16_pre(%xmm0, %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7, %xmm8, %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, %xmm14, @@ -904,6 +910,7 @@ ENTRY(camellia_ecb_enc_16way) %xmm15, %xmm14, %xmm13, %xmm12, %xmm11, %xmm10, %xmm9, %xmm8, %rsi); + FRAME_END ret; ENDPROC(camellia_ecb_enc_16way) @@ -913,6 +920,7 @@ ENTRY(camellia_ecb_dec_16way) * %rsi: dst (16 blocks) * %rdx: src (16 blocks) */ + FRAME_BEGIN cmpl $16, key_length(CTX); movl $32, %r8d; @@ -932,6 +940,7 @@ ENTRY(camellia_ecb_dec_16way) %xmm15, %xmm14, %xmm13, %xmm12, %xmm11, %xmm10, %xmm9, %xmm8, %rsi); + FRAME_END ret; ENDPROC(camellia_ecb_dec_16way) @@ -941,6 +950,7 @@ ENTRY(camellia_cbc_dec_16way) * %rsi: dst (16 blocks) * %rdx: src (16 blocks) */ + FRAME_BEGIN cmpl $16, key_length(CTX); movl $32, %r8d; @@ -981,6 +991,7 @@ ENTRY(camellia_cbc_dec_16way) %xmm15, %xmm14, %xmm13, %xmm12, %xmm11, %xmm10, %xmm9, %xmm8, %rsi); + FRAME_END ret; ENDPROC(camellia_cbc_dec_16way) @@ -997,6 +1008,7 @@ ENTRY(camellia_ctr_16way) * %rdx: src (16 blocks) * %rcx: iv (little endian, 128bit) */ + FRAME_BEGIN subq $(16 * 16), %rsp; movq %rsp, %rax; @@ -1092,6 +1104,7 @@ ENTRY(camellia_ctr_16way) %xmm15, %xmm14, %xmm13, %xmm12, %xmm11, %xmm10, %xmm9, %xmm8, %rsi); + FRAME_END ret; ENDPROC(camellia_ctr_16way) @@ -1112,6 +1125,7 @@ camellia_xts_crypt_16way: * %r8: index for input whitening key * %r9: pointer to __camellia_enc_blk16 or __camellia_dec_blk16 */ + FRAME_BEGIN subq $(16 * 16), %rsp; movq %rsp, %rax; @@ -1234,6 +1248,7 @@ camellia_xts_crypt_16way: %xmm15, %xmm14, %xmm13, %xmm12, %xmm11, %xmm10, %xmm9, %xmm8, %rsi); + FRAME_END ret; ENDPROC(camellia_xts_crypt_16way) diff --git a/arch/x86/crypto/camellia-aesni-avx2-asm_64.S b/arch/x86/crypto/camellia-aesni-avx2-asm_64.S index 0e0b8863a34b..16186c18656d 100644 --- a/arch/x86/crypto/camellia-aesni-avx2-asm_64.S +++ b/arch/x86/crypto/camellia-aesni-avx2-asm_64.S @@ -11,6 +11,7 @@ */ #include +#include #define CAMELLIA_TABLE_BYTE_LEN 272 @@ -766,6 +767,7 @@ __camellia_enc_blk32: * %ymm0..%ymm15: 32 encrypted blocks, order swapped: * 7, 8, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8 */ + FRAME_BEGIN leaq 8 * 32(%rax), %rcx; @@ -820,6 +822,7 @@ __camellia_enc_blk32: %ymm8, %ymm9, %ymm10, %ymm11, %ymm12, %ymm13, %ymm14, %ymm15, (key_table)(CTX, %r8, 8), (%rax), 1 * 32(%rax)); + FRAME_END ret; .align 8 @@ -852,6 +855,7 @@ __camellia_dec_blk32: * %ymm0..%ymm15: 16 plaintext blocks, order swapped: * 7, 8, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8 */ + FRAME_BEGIN leaq 8 * 32(%rax), %rcx; @@ -905,6 +909,7 @@ __camellia_dec_blk32: %ymm8, %ymm9, %ymm10, %ymm11, %ymm12, %ymm13, %ymm14, %ymm15, (key_table)(CTX), (%rax), 1 * 32(%rax)); + FRAME_END ret; .align 8 @@ -930,6 +935,7 @@ ENTRY(camellia_ecb_enc_32way) * %rsi: dst (32 blocks) * %rdx: src (32 blocks) */ + FRAME_BEGIN vzeroupper; @@ -948,6 +954,7 @@ ENTRY(camellia_ecb_enc_32way) vzeroupper; + FRAME_END ret; ENDPROC(camellia_ecb_enc_32way) @@ -957,6 +964,7 @@ ENTRY(camellia_ecb_dec_32way) * %rsi: dst (32 blocks) * %rdx: src (32 blocks) */ + FRAME_BEGIN vzeroupper; @@ -980,6 +988,7 @@ ENTRY(camellia_ecb_dec_32way) vzeroupper; + FRAME_END ret; ENDPROC(camellia_ecb_dec_32way) @@ -989,6 +998,7 @@ ENTRY(camellia_cbc_dec_32way) * %rsi: dst (32 blocks) * %rdx: src (32 blocks) */ + FRAME_BEGIN vzeroupper; @@ -1046,6 +1056,7 @@ ENTRY(camellia_cbc_dec_32way) vzeroupper; + FRAME_END ret; ENDPROC(camellia_cbc_dec_32way) @@ -1070,6 +1081,7 @@ ENTRY(camellia_ctr_32way) * %rdx: src (32 blocks) * %rcx: iv (little endian, 128bit) */ + FRAME_BEGIN vzeroupper; @@ -1184,6 +1196,7 @@ ENTRY(camellia_ctr_32way) vzeroupper; + FRAME_END ret; ENDPROC(camellia_ctr_32way) @@ -1216,6 +1229,7 @@ camellia_xts_crypt_32way: * %r8: index for input whitening key * %r9: pointer to __camellia_enc_blk32 or __camellia_dec_blk32 */ + FRAME_BEGIN vzeroupper; @@ -1349,6 +1363,7 @@ camellia_xts_crypt_32way: vzeroupper; + FRAME_END ret; ENDPROC(camellia_xts_crypt_32way) diff --git a/arch/x86/crypto/cast5-avx-x86_64-asm_64.S b/arch/x86/crypto/cast5-avx-x86_64-asm_64.S index c35fd5d6ecd2..14fa1966bf01 100644 --- a/arch/x86/crypto/cast5-avx-x86_64-asm_64.S +++ b/arch/x86/crypto/cast5-avx-x86_64-asm_64.S @@ -24,6 +24,7 @@ */ #include +#include .file "cast5-avx-x86_64-asm_64.S" @@ -365,6 +366,7 @@ ENTRY(cast5_ecb_enc_16way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN movq %rsi, %r11; @@ -388,6 +390,7 @@ ENTRY(cast5_ecb_enc_16way) vmovdqu RR4, (6*4*4)(%r11); vmovdqu RL4, (7*4*4)(%r11); + FRAME_END ret; ENDPROC(cast5_ecb_enc_16way) @@ -398,6 +401,7 @@ ENTRY(cast5_ecb_dec_16way) * %rdx: src */ + FRAME_BEGIN movq %rsi, %r11; vmovdqu (0*4*4)(%rdx), RL1; @@ -420,6 +424,7 @@ ENTRY(cast5_ecb_dec_16way) vmovdqu RR4, (6*4*4)(%r11); vmovdqu RL4, (7*4*4)(%r11); + FRAME_END ret; ENDPROC(cast5_ecb_dec_16way) @@ -429,6 +434,7 @@ ENTRY(cast5_cbc_dec_16way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN pushq %r12; @@ -469,6 +475,7 @@ ENTRY(cast5_cbc_dec_16way) popq %r12; + FRAME_END ret; ENDPROC(cast5_cbc_dec_16way) @@ -479,6 +486,7 @@ ENTRY(cast5_ctr_16way) * %rdx: src * %rcx: iv (big endian, 64bit) */ + FRAME_BEGIN pushq %r12; @@ -542,5 +550,6 @@ ENTRY(cast5_ctr_16way) popq %r12; + FRAME_END ret; ENDPROC(cast5_ctr_16way) diff --git a/arch/x86/crypto/cast6-avx-x86_64-asm_64.S b/arch/x86/crypto/cast6-avx-x86_64-asm_64.S index e3531f833951..c419389889cd 100644 --- a/arch/x86/crypto/cast6-avx-x86_64-asm_64.S +++ b/arch/x86/crypto/cast6-avx-x86_64-asm_64.S @@ -24,6 +24,7 @@ */ #include +#include #include "glue_helper-asm-avx.S" .file "cast6-avx-x86_64-asm_64.S" @@ -349,6 +350,7 @@ ENTRY(cast6_ecb_enc_8way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN movq %rsi, %r11; @@ -358,6 +360,7 @@ ENTRY(cast6_ecb_enc_8way) store_8way(%r11, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(cast6_ecb_enc_8way) @@ -367,6 +370,7 @@ ENTRY(cast6_ecb_dec_8way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN movq %rsi, %r11; @@ -376,6 +380,7 @@ ENTRY(cast6_ecb_dec_8way) store_8way(%r11, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(cast6_ecb_dec_8way) @@ -385,6 +390,7 @@ ENTRY(cast6_cbc_dec_8way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN pushq %r12; @@ -399,6 +405,7 @@ ENTRY(cast6_cbc_dec_8way) popq %r12; + FRAME_END ret; ENDPROC(cast6_cbc_dec_8way) @@ -409,6 +416,7 @@ ENTRY(cast6_ctr_8way) * %rdx: src * %rcx: iv (little endian, 128bit) */ + FRAME_BEGIN pushq %r12; @@ -424,6 +432,7 @@ ENTRY(cast6_ctr_8way) popq %r12; + FRAME_END ret; ENDPROC(cast6_ctr_8way) @@ -434,6 +443,7 @@ ENTRY(cast6_xts_enc_8way) * %rdx: src * %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸)) */ + FRAME_BEGIN movq %rsi, %r11; @@ -446,6 +456,7 @@ ENTRY(cast6_xts_enc_8way) /* dst <= regs xor IVs(in dst) */ store_xts_8way(%r11, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(cast6_xts_enc_8way) @@ -456,6 +467,7 @@ ENTRY(cast6_xts_dec_8way) * %rdx: src * %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸)) */ + FRAME_BEGIN movq %rsi, %r11; @@ -468,5 +480,6 @@ ENTRY(cast6_xts_dec_8way) /* dst <= regs xor IVs(in dst) */ store_xts_8way(%r11, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(cast6_xts_dec_8way) diff --git a/arch/x86/crypto/ghash-clmulni-intel_asm.S b/arch/x86/crypto/ghash-clmulni-intel_asm.S index 5d1e0075ac24..eed55c8cca4f 100644 --- a/arch/x86/crypto/ghash-clmulni-intel_asm.S +++ b/arch/x86/crypto/ghash-clmulni-intel_asm.S @@ -18,6 +18,7 @@ #include #include +#include .data @@ -94,6 +95,7 @@ ENDPROC(__clmul_gf128mul_ble) /* void clmul_ghash_mul(char *dst, const u128 *shash) */ ENTRY(clmul_ghash_mul) + FRAME_BEGIN movups (%rdi), DATA movups (%rsi), SHASH movaps .Lbswap_mask, BSWAP @@ -101,6 +103,7 @@ ENTRY(clmul_ghash_mul) call __clmul_gf128mul_ble PSHUFB_XMM BSWAP DATA movups DATA, (%rdi) + FRAME_END ret ENDPROC(clmul_ghash_mul) @@ -109,6 +112,7 @@ ENDPROC(clmul_ghash_mul) * const u128 *shash); */ ENTRY(clmul_ghash_update) + FRAME_BEGIN cmp $16, %rdx jb .Lupdate_just_ret # check length movaps .Lbswap_mask, BSWAP @@ -128,5 +132,6 @@ ENTRY(clmul_ghash_update) PSHUFB_XMM BSWAP DATA movups DATA, (%rdi) .Lupdate_just_ret: + FRAME_END ret ENDPROC(clmul_ghash_update) diff --git a/arch/x86/crypto/serpent-avx-x86_64-asm_64.S b/arch/x86/crypto/serpent-avx-x86_64-asm_64.S index 2f202f49872b..8be571808342 100644 --- a/arch/x86/crypto/serpent-avx-x86_64-asm_64.S +++ b/arch/x86/crypto/serpent-avx-x86_64-asm_64.S @@ -24,6 +24,7 @@ */ #include +#include #include "glue_helper-asm-avx.S" .file "serpent-avx-x86_64-asm_64.S" @@ -681,6 +682,7 @@ ENTRY(serpent_ecb_enc_8way_avx) * %rsi: dst * %rdx: src */ + FRAME_BEGIN load_8way(%rdx, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); @@ -688,6 +690,7 @@ ENTRY(serpent_ecb_enc_8way_avx) store_8way(%rsi, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(serpent_ecb_enc_8way_avx) @@ -697,6 +700,7 @@ ENTRY(serpent_ecb_dec_8way_avx) * %rsi: dst * %rdx: src */ + FRAME_BEGIN load_8way(%rdx, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); @@ -704,6 +708,7 @@ ENTRY(serpent_ecb_dec_8way_avx) store_8way(%rsi, RC1, RD1, RB1, RE1, RC2, RD2, RB2, RE2); + FRAME_END ret; ENDPROC(serpent_ecb_dec_8way_avx) @@ -713,6 +718,7 @@ ENTRY(serpent_cbc_dec_8way_avx) * %rsi: dst * %rdx: src */ + FRAME_BEGIN load_8way(%rdx, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); @@ -720,6 +726,7 @@ ENTRY(serpent_cbc_dec_8way_avx) store_cbc_8way(%rdx, %rsi, RC1, RD1, RB1, RE1, RC2, RD2, RB2, RE2); + FRAME_END ret; ENDPROC(serpent_cbc_dec_8way_avx) @@ -730,6 +737,7 @@ ENTRY(serpent_ctr_8way_avx) * %rdx: src * %rcx: iv (little endian, 128bit) */ + FRAME_BEGIN load_ctr_8way(%rcx, .Lbswap128_mask, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2, RK0, RK1, RK2); @@ -738,6 +746,7 @@ ENTRY(serpent_ctr_8way_avx) store_ctr_8way(%rdx, %rsi, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(serpent_ctr_8way_avx) @@ -748,6 +757,7 @@ ENTRY(serpent_xts_enc_8way_avx) * %rdx: src * %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸)) */ + FRAME_BEGIN /* regs <= src, dst <= IVs, regs <= regs xor IVs */ load_xts_8way(%rcx, %rdx, %rsi, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2, @@ -758,6 +768,7 @@ ENTRY(serpent_xts_enc_8way_avx) /* dst <= regs xor IVs(in dst) */ store_xts_8way(%rsi, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(serpent_xts_enc_8way_avx) @@ -768,6 +779,7 @@ ENTRY(serpent_xts_dec_8way_avx) * %rdx: src * %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸)) */ + FRAME_BEGIN /* regs <= src, dst <= IVs, regs <= regs xor IVs */ load_xts_8way(%rcx, %rdx, %rsi, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2, @@ -778,5 +790,6 @@ ENTRY(serpent_xts_dec_8way_avx) /* dst <= regs xor IVs(in dst) */ store_xts_8way(%rsi, RC1, RD1, RB1, RE1, RC2, RD2, RB2, RE2); + FRAME_END ret; ENDPROC(serpent_xts_dec_8way_avx) diff --git a/arch/x86/crypto/serpent-avx2-asm_64.S b/arch/x86/crypto/serpent-avx2-asm_64.S index b222085cccac..97c48add33ed 100644 --- a/arch/x86/crypto/serpent-avx2-asm_64.S +++ b/arch/x86/crypto/serpent-avx2-asm_64.S @@ -15,6 +15,7 @@ */ #include +#include #include "glue_helper-asm-avx2.S" .file "serpent-avx2-asm_64.S" @@ -673,6 +674,7 @@ ENTRY(serpent_ecb_enc_16way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN vzeroupper; @@ -684,6 +686,7 @@ ENTRY(serpent_ecb_enc_16way) vzeroupper; + FRAME_END ret; ENDPROC(serpent_ecb_enc_16way) @@ -693,6 +696,7 @@ ENTRY(serpent_ecb_dec_16way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN vzeroupper; @@ -704,6 +708,7 @@ ENTRY(serpent_ecb_dec_16way) vzeroupper; + FRAME_END ret; ENDPROC(serpent_ecb_dec_16way) @@ -713,6 +718,7 @@ ENTRY(serpent_cbc_dec_16way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN vzeroupper; @@ -725,6 +731,7 @@ ENTRY(serpent_cbc_dec_16way) vzeroupper; + FRAME_END ret; ENDPROC(serpent_cbc_dec_16way) @@ -735,6 +742,7 @@ ENTRY(serpent_ctr_16way) * %rdx: src (16 blocks) * %rcx: iv (little endian, 128bit) */ + FRAME_BEGIN vzeroupper; @@ -748,6 +756,7 @@ ENTRY(serpent_ctr_16way) vzeroupper; + FRAME_END ret; ENDPROC(serpent_ctr_16way) @@ -758,6 +767,7 @@ ENTRY(serpent_xts_enc_16way) * %rdx: src (16 blocks) * %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸)) */ + FRAME_BEGIN vzeroupper; @@ -772,6 +782,7 @@ ENTRY(serpent_xts_enc_16way) vzeroupper; + FRAME_END ret; ENDPROC(serpent_xts_enc_16way) @@ -782,6 +793,7 @@ ENTRY(serpent_xts_dec_16way) * %rdx: src (16 blocks) * %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸)) */ + FRAME_BEGIN vzeroupper; @@ -796,5 +808,6 @@ ENTRY(serpent_xts_dec_16way) vzeroupper; + FRAME_END ret; ENDPROC(serpent_xts_dec_16way) diff --git a/arch/x86/crypto/sha-mb/sha1_mb_mgr_flush_avx2.S b/arch/x86/crypto/sha-mb/sha1_mb_mgr_flush_avx2.S index 672eaeb258a5..96df6a39d7e2 100644 --- a/arch/x86/crypto/sha-mb/sha1_mb_mgr_flush_avx2.S +++ b/arch/x86/crypto/sha-mb/sha1_mb_mgr_flush_avx2.S @@ -52,6 +52,7 @@ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include +#include #include "sha1_mb_mgr_datastruct.S" @@ -103,6 +104,7 @@ offset = \_offset # JOB* sha1_mb_mgr_flush_avx2(MB_MGR *state) # arg 1 : rcx : state ENTRY(sha1_mb_mgr_flush_avx2) + FRAME_BEGIN push %rbx # If bit (32+3) is set, then all lanes are empty @@ -212,6 +214,7 @@ len_is_0: return: pop %rbx + FRAME_END ret return_null: diff --git a/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S b/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S index c3b944781d3f..1435acf46f22 100644 --- a/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S +++ b/arch/x86/crypto/sha-mb/sha1_mb_mgr_submit_avx2.S @@ -53,6 +53,7 @@ */ #include +#include #include "sha1_mb_mgr_datastruct.S" @@ -98,6 +99,7 @@ lane_data = %r10 # arg 1 : rcx : state # arg 2 : rdx : job ENTRY(sha1_mb_mgr_submit_avx2) + FRAME_BEGIN push %rbx push %r12 @@ -192,6 +194,7 @@ len_is_0: return: pop %r12 pop %rbx + FRAME_END ret return_null: diff --git a/arch/x86/crypto/twofish-avx-x86_64-asm_64.S b/arch/x86/crypto/twofish-avx-x86_64-asm_64.S index 05058134c443..dc66273e610d 100644 --- a/arch/x86/crypto/twofish-avx-x86_64-asm_64.S +++ b/arch/x86/crypto/twofish-avx-x86_64-asm_64.S @@ -24,6 +24,7 @@ */ #include +#include #include "glue_helper-asm-avx.S" .file "twofish-avx-x86_64-asm_64.S" @@ -333,6 +334,7 @@ ENTRY(twofish_ecb_enc_8way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN movq %rsi, %r11; @@ -342,6 +344,7 @@ ENTRY(twofish_ecb_enc_8way) store_8way(%r11, RC1, RD1, RA1, RB1, RC2, RD2, RA2, RB2); + FRAME_END ret; ENDPROC(twofish_ecb_enc_8way) @@ -351,6 +354,7 @@ ENTRY(twofish_ecb_dec_8way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN movq %rsi, %r11; @@ -360,6 +364,7 @@ ENTRY(twofish_ecb_dec_8way) store_8way(%r11, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(twofish_ecb_dec_8way) @@ -369,6 +374,7 @@ ENTRY(twofish_cbc_dec_8way) * %rsi: dst * %rdx: src */ + FRAME_BEGIN pushq %r12; @@ -383,6 +389,7 @@ ENTRY(twofish_cbc_dec_8way) popq %r12; + FRAME_END ret; ENDPROC(twofish_cbc_dec_8way) @@ -393,6 +400,7 @@ ENTRY(twofish_ctr_8way) * %rdx: src * %rcx: iv (little endian, 128bit) */ + FRAME_BEGIN pushq %r12; @@ -408,6 +416,7 @@ ENTRY(twofish_ctr_8way) popq %r12; + FRAME_END ret; ENDPROC(twofish_ctr_8way) @@ -418,6 +427,7 @@ ENTRY(twofish_xts_enc_8way) * %rdx: src * %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸)) */ + FRAME_BEGIN movq %rsi, %r11; @@ -430,6 +440,7 @@ ENTRY(twofish_xts_enc_8way) /* dst <= regs xor IVs(in dst) */ store_xts_8way(%r11, RC1, RD1, RA1, RB1, RC2, RD2, RA2, RB2); + FRAME_END ret; ENDPROC(twofish_xts_enc_8way) @@ -440,6 +451,7 @@ ENTRY(twofish_xts_dec_8way) * %rdx: src * %rcx: iv (t ⊕ αⁿ ∈ GF(2¹²⁸)) */ + FRAME_BEGIN movq %rsi, %r11; @@ -452,5 +464,6 @@ ENTRY(twofish_xts_dec_8way) /* dst <= regs xor IVs(in dst) */ store_xts_8way(%r11, RA1, RB1, RC1, RD1, RA2, RB2, RC2, RD2); + FRAME_END ret; ENDPROC(twofish_xts_dec_8way) From 058fb73274f9e7eb72acc9836cbb2c4a9f9659a0 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:20 -0600 Subject: [PATCH 12/52] x86/asm/entry: Create stack frames in thunk functions Thunk functions are callable non-leaf functions that don't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Also they aren't annotated as ELF callable functions which can confuse tooling. Create stack frames for them when CONFIG_FRAME_POINTER is enabled and add the ELF function type. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/4373e5bff459b9fd66ce5d45bfcc881a5c202643.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/entry/thunk_64.S | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/entry/thunk_64.S b/arch/x86/entry/thunk_64.S index efb2b932b748..98df1fa8825c 100644 --- a/arch/x86/entry/thunk_64.S +++ b/arch/x86/entry/thunk_64.S @@ -8,11 +8,14 @@ #include #include "calling.h" #include +#include /* rdi: arg1 ... normal C conventions. rax is saved/restored. */ .macro THUNK name, func, put_ret_addr_in_rdi=0 .globl \name + .type \name, @function \name: + FRAME_BEGIN /* this one pushes 9 elems, the next one would be %rIP */ pushq %rdi @@ -62,6 +65,7 @@ restore: popq %rdx popq %rsi popq %rdi + FRAME_END ret _ASM_NOKPROBE(restore) #endif From 13523309495cdbd57a0d344c0d5d574987af007f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:21 -0600 Subject: [PATCH 13/52] x86/asm/acpi: Create a stack frame in do_suspend_lowlevel() do_suspend_lowlevel() is a callable non-leaf function which doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create a stack frame for it when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Acked-by: Pavel Machek Acked-by: Rafael J. Wysocki Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Len Brown Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/7383d87dd40a460e0d757a0793498b9d06a7ee0d.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/acpi/wakeup_64.S | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S index 8c35df468104..169963f471bb 100644 --- a/arch/x86/kernel/acpi/wakeup_64.S +++ b/arch/x86/kernel/acpi/wakeup_64.S @@ -5,6 +5,7 @@ #include #include #include +#include # Copyright 2003 Pavel Machek , distribute under GPLv2 @@ -39,6 +40,7 @@ bogus_64_magic: jmp bogus_64_magic ENTRY(do_suspend_lowlevel) + FRAME_BEGIN subq $8, %rsp xorl %eax, %eax call save_processor_state @@ -109,6 +111,7 @@ ENTRY(do_suspend_lowlevel) xorl %eax, %eax addq $8, %rsp + FRAME_END jmp restore_processor_state ENDPROC(do_suspend_lowlevel) From 3387a535ce629906d849864ef6a3c3437a645cb5 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:22 -0600 Subject: [PATCH 14/52] x86/asm: Create stack frames in rwsem functions rwsem.S has several callable non-leaf functions which don't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create stack frames for them when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/ad0932bbead975b15f9578e4f2cf2ee5961eb840.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/lib/rwsem.S | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/x86/lib/rwsem.S b/arch/x86/lib/rwsem.S index 40027db99140..be110efa0096 100644 --- a/arch/x86/lib/rwsem.S +++ b/arch/x86/lib/rwsem.S @@ -15,6 +15,7 @@ #include #include +#include #define __ASM_HALF_REG(reg) __ASM_SEL(reg, e##reg) #define __ASM_HALF_SIZE(inst) __ASM_SEL(inst##w, inst##l) @@ -84,24 +85,29 @@ /* Fix up special calling conventions */ ENTRY(call_rwsem_down_read_failed) + FRAME_BEGIN save_common_regs __ASM_SIZE(push,) %__ASM_REG(dx) movq %rax,%rdi call rwsem_down_read_failed __ASM_SIZE(pop,) %__ASM_REG(dx) restore_common_regs + FRAME_END ret ENDPROC(call_rwsem_down_read_failed) ENTRY(call_rwsem_down_write_failed) + FRAME_BEGIN save_common_regs movq %rax,%rdi call rwsem_down_write_failed restore_common_regs + FRAME_END ret ENDPROC(call_rwsem_down_write_failed) ENTRY(call_rwsem_wake) + FRAME_BEGIN /* do nothing if still outstanding active readers */ __ASM_HALF_SIZE(dec) %__ASM_HALF_REG(dx) jnz 1f @@ -109,15 +115,18 @@ ENTRY(call_rwsem_wake) movq %rax,%rdi call rwsem_wake restore_common_regs -1: ret +1: FRAME_END + ret ENDPROC(call_rwsem_wake) ENTRY(call_rwsem_downgrade_wake) + FRAME_BEGIN save_common_regs __ASM_SIZE(push,) %__ASM_REG(dx) movq %rax,%rdi call rwsem_downgrade_wake __ASM_SIZE(pop,) %__ASM_REG(dx) restore_common_regs + FRAME_END ret ENDPROC(call_rwsem_downgrade_wake) From 779c433b8ea5c9fdfb892265b2ca6213d1f12ff8 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:23 -0600 Subject: [PATCH 15/52] x86/asm/efi: Create a stack frame in efi_call() efi_call() is a callable non-leaf function which doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create a stack frame for it when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf Reviewed-by: Matt Fleming Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/2294b6fad60eea4cc862eddc8e98a1324e6eeeca.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/platform/efi/efi_stub_64.S | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/platform/efi/efi_stub_64.S b/arch/x86/platform/efi/efi_stub_64.S index 86d0f9e08dd9..0df2dcc18404 100644 --- a/arch/x86/platform/efi/efi_stub_64.S +++ b/arch/x86/platform/efi/efi_stub_64.S @@ -11,6 +11,7 @@ #include #include #include +#include #define SAVE_XMM \ mov %rsp, %rax; \ @@ -74,6 +75,7 @@ .endm ENTRY(efi_call) + FRAME_BEGIN SAVE_XMM mov (%rsp), %rax mov 8(%rax), %rax @@ -88,6 +90,7 @@ ENTRY(efi_call) RESTORE_PGT addq $48, %rsp RESTORE_XMM + FRAME_END ret ENDPROC(efi_call) From ef0f3ed5a4acfb24740480bf2e50b178724f094d Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:24 -0600 Subject: [PATCH 16/52] x86/asm/power: Create stack frames in hibernate_asm_64.S swsusp_arch_suspend() and restore_registers() are callable non-leaf functions which don't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Also they aren't annotated as ELF callable functions which can confuse tooling. Create a stack frame for them when CONFIG_FRAME_POINTER is enabled and give them proper ELF function annotations. Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Acked-by: Pavel Machek Acked-by: Rafael J. Wysocki Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/bdad00205897dc707aebe9e9e39757085e2bf999.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/power/hibernate_asm_64.S | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/power/hibernate_asm_64.S b/arch/x86/power/hibernate_asm_64.S index e2386cb4e0c3..4400a43b9e28 100644 --- a/arch/x86/power/hibernate_asm_64.S +++ b/arch/x86/power/hibernate_asm_64.S @@ -21,8 +21,10 @@ #include #include #include +#include ENTRY(swsusp_arch_suspend) + FRAME_BEGIN movq $saved_context, %rax movq %rsp, pt_regs_sp(%rax) movq %rbp, pt_regs_bp(%rax) @@ -50,7 +52,9 @@ ENTRY(swsusp_arch_suspend) movq %rax, restore_cr3(%rip) call swsusp_save + FRAME_END ret +ENDPROC(swsusp_arch_suspend) ENTRY(restore_image) /* switch to temporary page tables */ @@ -107,6 +111,7 @@ ENTRY(core_restore_code) */ ENTRY(restore_registers) + FRAME_BEGIN /* go back to the original page tables */ movq %rbx, %cr3 @@ -147,4 +152,6 @@ ENTRY(restore_registers) /* tell the hibernation core that we've just restored the memory */ movq %rax, in_suspend(%rip) + FRAME_END ret +ENDPROC(restore_registers) From f05058c4d652b619adfda6c78d8f5b341169c264 Mon Sep 17 00:00:00 2001 From: Chris J Arges Date: Thu, 21 Jan 2016 16:49:25 -0600 Subject: [PATCH 17/52] x86/uaccess: Add stack frame output operand in get_user() inline asm Numerous 'call without frame pointer save/setup' warnings are introduced by stacktool because of functions using the get_user() macro. Bad stack traces could occur due to lack of or misplacement of stack frame setup code. This patch forces a stack frame to be created before the inline asm code if CONFIG_FRAME_POINTER is enabled by listing the stack pointer as an output operand for the get_user() inline assembly statement. Signed-off-by: Chris J Arges Signed-off-by: Josh Poimboeuf Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/bc85501f221ee512670797c7f110022e64b12c81.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/uaccess.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index a4a30e4b2d34..9bbb3b2d0372 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -179,10 +179,11 @@ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) ({ \ int __ret_gu; \ register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX); \ + register void *__sp asm(_ASM_SP); \ __chk_user_ptr(ptr); \ might_fault(); \ - asm volatile("call __get_user_%P3" \ - : "=a" (__ret_gu), "=r" (__val_gu) \ + asm volatile("call __get_user_%P4" \ + : "=a" (__ret_gu), "=r" (__val_gu), "+r" (__sp) \ : "0" (ptr), "i" (sizeof(*(ptr)))); \ (x) = (__force __typeof__(*(ptr))) __val_gu; \ __builtin_expect(__ret_gu, 0); \ From 2d8fe90a1b96d52c2a3f719c385b846b02f0bcd8 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:26 -0600 Subject: [PATCH 18/52] x86/asm/bpf: Annotate callable functions bpf_jit.S has several functions which can be called from C code. Give them proper ELF annotations. Signed-off-by: Josh Poimboeuf Acked-by: Alexei Starovoitov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/bbe1de0c299fecd4fc9a1766bae8be2647bedb01.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/net/bpf_jit.S | 39 ++++++++++++++++----------------------- 1 file changed, 16 insertions(+), 23 deletions(-) diff --git a/arch/x86/net/bpf_jit.S b/arch/x86/net/bpf_jit.S index 4093216b3791..eb4a3bd293eb 100644 --- a/arch/x86/net/bpf_jit.S +++ b/arch/x86/net/bpf_jit.S @@ -22,15 +22,16 @@ 32 /* space for rbx,r13,r14,r15 */ + \ 8 /* space for skb_copy_bits */) -sk_load_word: - .globl sk_load_word +#define FUNC(name) \ + .globl name; \ + .type name, @function; \ + name: +FUNC(sk_load_word) test %esi,%esi js bpf_slow_path_word_neg -sk_load_word_positive_offset: - .globl sk_load_word_positive_offset - +FUNC(sk_load_word_positive_offset) mov %r9d,%eax # hlen sub %esi,%eax # hlen - offset cmp $3,%eax @@ -39,15 +40,11 @@ sk_load_word_positive_offset: bswap %eax /* ntohl() */ ret -sk_load_half: - .globl sk_load_half - +FUNC(sk_load_half) test %esi,%esi js bpf_slow_path_half_neg -sk_load_half_positive_offset: - .globl sk_load_half_positive_offset - +FUNC(sk_load_half_positive_offset) mov %r9d,%eax sub %esi,%eax # hlen - offset cmp $1,%eax @@ -56,15 +53,11 @@ sk_load_half_positive_offset: rol $8,%ax # ntohs() ret -sk_load_byte: - .globl sk_load_byte - +FUNC(sk_load_byte) test %esi,%esi js bpf_slow_path_byte_neg -sk_load_byte_positive_offset: - .globl sk_load_byte_positive_offset - +FUNC(sk_load_byte_positive_offset) cmp %esi,%r9d /* if (offset >= hlen) goto bpf_slow_path_byte */ jle bpf_slow_path_byte movzbl (SKBDATA,%rsi),%eax @@ -120,8 +113,8 @@ bpf_slow_path_byte: bpf_slow_path_word_neg: cmp SKF_MAX_NEG_OFF, %esi /* test range */ jl bpf_error /* offset lower -> error */ -sk_load_word_negative_offset: - .globl sk_load_word_negative_offset + +FUNC(sk_load_word_negative_offset) sk_negative_common(4) mov (%rax), %eax bswap %eax @@ -130,8 +123,8 @@ sk_load_word_negative_offset: bpf_slow_path_half_neg: cmp SKF_MAX_NEG_OFF, %esi jl bpf_error -sk_load_half_negative_offset: - .globl sk_load_half_negative_offset + +FUNC(sk_load_half_negative_offset) sk_negative_common(2) mov (%rax),%ax rol $8,%ax @@ -141,8 +134,8 @@ sk_load_half_negative_offset: bpf_slow_path_byte_neg: cmp SKF_MAX_NEG_OFF, %esi jl bpf_error -sk_load_byte_negative_offset: - .globl sk_load_byte_negative_offset + +FUNC(sk_load_byte_negative_offset) sk_negative_common(1) movzbl (%rax), %eax ret From d21001cc15ba9f63b0334d60942278587471a451 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:27 -0600 Subject: [PATCH 19/52] x86/asm/bpf: Create stack frames in bpf_jit.S bpf_jit.S has several callable non-leaf functions which don't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create a stack frame before the call instructions when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf Acked-by: Alexei Starovoitov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/fa4c41976b438b51954cb8021f06bceb1d1d66cc.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/net/bpf_jit.S | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/net/bpf_jit.S b/arch/x86/net/bpf_jit.S index eb4a3bd293eb..f2a7faf4706e 100644 --- a/arch/x86/net/bpf_jit.S +++ b/arch/x86/net/bpf_jit.S @@ -8,6 +8,7 @@ * of the License. */ #include +#include /* * Calling convention : @@ -65,16 +66,18 @@ FUNC(sk_load_byte_positive_offset) /* rsi contains offset and can be scratched */ #define bpf_slow_path_common(LEN) \ + lea -MAX_BPF_STACK + 32(%rbp), %rdx;\ + FRAME_BEGIN; \ mov %rbx, %rdi; /* arg1 == skb */ \ push %r9; \ push SKBDATA; \ /* rsi already has offset */ \ mov $LEN,%ecx; /* len */ \ - lea - MAX_BPF_STACK + 32(%rbp),%rdx; \ call skb_copy_bits; \ test %eax,%eax; \ pop SKBDATA; \ - pop %r9; + pop %r9; \ + FRAME_END bpf_slow_path_word: @@ -99,6 +102,7 @@ bpf_slow_path_byte: ret #define sk_negative_common(SIZE) \ + FRAME_BEGIN; \ mov %rbx, %rdi; /* arg1 == skb */ \ push %r9; \ push SKBDATA; \ @@ -108,6 +112,7 @@ bpf_slow_path_byte: test %rax,%rax; \ pop SKBDATA; \ pop %r9; \ + FRAME_END; \ jz bpf_error bpf_slow_path_word_neg: From c1c355ce14c037666fbcb9453d9067c86bbdda5c Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:28 -0600 Subject: [PATCH 20/52] x86/kprobes: Get rid of kretprobe_trampoline_holder() The kretprobe_trampoline_holder() wrapper around kretprobe_trampoline() isn't used anywhere and adds some unnecessary frame pointer instructions which never execute. Instead, just make kretprobe_trampoline() a proper ELF function. Signed-off-by: Josh Poimboeuf Acked-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Anil S Keshavamurthy Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: David S. Miller Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/92d921b102fb865a7c254cfde9e4a0a72b9a781e.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/kprobes/core.c | 57 +++++++++++++++++----------------- 1 file changed, 28 insertions(+), 29 deletions(-) diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 1deffe6cc873..5b187dfbfc8b 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -671,38 +671,37 @@ NOKPROBE_SYMBOL(kprobe_int3_handler); * When a retprobed function returns, this code saves registers and * calls trampoline_handler() runs, which calls the kretprobe's handler. */ -static void __used kretprobe_trampoline_holder(void) -{ - asm volatile ( - ".global kretprobe_trampoline\n" - "kretprobe_trampoline: \n" +asm( + ".global kretprobe_trampoline\n" + ".type kretprobe_trampoline, @function\n" + "kretprobe_trampoline:\n" #ifdef CONFIG_X86_64 - /* We don't bother saving the ss register */ - " pushq %rsp\n" - " pushfq\n" - SAVE_REGS_STRING - " movq %rsp, %rdi\n" - " call trampoline_handler\n" - /* Replace saved sp with true return address. */ - " movq %rax, 152(%rsp)\n" - RESTORE_REGS_STRING - " popfq\n" + /* We don't bother saving the ss register */ + " pushq %rsp\n" + " pushfq\n" + SAVE_REGS_STRING + " movq %rsp, %rdi\n" + " call trampoline_handler\n" + /* Replace saved sp with true return address. */ + " movq %rax, 152(%rsp)\n" + RESTORE_REGS_STRING + " popfq\n" #else - " pushf\n" - SAVE_REGS_STRING - " movl %esp, %eax\n" - " call trampoline_handler\n" - /* Move flags to cs */ - " movl 56(%esp), %edx\n" - " movl %edx, 52(%esp)\n" - /* Replace saved flags with true return address. */ - " movl %eax, 56(%esp)\n" - RESTORE_REGS_STRING - " popf\n" + " pushf\n" + SAVE_REGS_STRING + " movl %esp, %eax\n" + " call trampoline_handler\n" + /* Move flags to cs */ + " movl 56(%esp), %edx\n" + " movl %edx, 52(%esp)\n" + /* Replace saved flags with true return address. */ + " movl %eax, 56(%esp)\n" + RESTORE_REGS_STRING + " popf\n" #endif - " ret\n"); -} -NOKPROBE_SYMBOL(kretprobe_trampoline_holder); + " ret\n" + ".size kretprobe_trampoline, .-kretprobe_trampoline\n" +); NOKPROBE_SYMBOL(kretprobe_trampoline); /* From 1482a0825bdf82dab4074bd3c824f4c87cbdf848 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:29 -0600 Subject: [PATCH 21/52] x86/kvm: Set ELF function type for fastop functions The callable functions created with the FOP* and FASTOP* macros are missing ELF function annotations, which confuses tools like stacktool. Properly annotate them. This adds some additional labels to the assembly, but the generated binary code is unchanged (with the exception of instructions which have embedded references to __LINE__). Signed-off-by: Josh Poimboeuf Acked-by: Paolo Bonzini Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: Gleb Natapov Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kvm@vger.kernel.org Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/e399651c89ace54906c203c0557f66ed6ea3ce8d.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kvm/emulate.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 1505587d06e9..aa4d72667878 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -309,23 +309,29 @@ static void invalidate_registers(struct x86_emulate_ctxt *ctxt) static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)); -#define FOP_ALIGN ".align " __stringify(FASTOP_SIZE) " \n\t" +#define FOP_FUNC(name) \ + ".align " __stringify(FASTOP_SIZE) " \n\t" \ + ".type " name ", @function \n\t" \ + name ":\n\t" + #define FOP_RET "ret \n\t" #define FOP_START(op) \ extern void em_##op(struct fastop *fake); \ asm(".pushsection .text, \"ax\" \n\t" \ ".global em_" #op " \n\t" \ - FOP_ALIGN \ - "em_" #op ": \n\t" + FOP_FUNC("em_" #op) #define FOP_END \ ".popsection") -#define FOPNOP() FOP_ALIGN FOP_RET +#define FOPNOP() \ + FOP_FUNC(__stringify(__UNIQUE_ID(nop))) \ + FOP_RET #define FOP1E(op, dst) \ - FOP_ALIGN "10: " #op " %" #dst " \n\t" FOP_RET + FOP_FUNC(#op "_" #dst) \ + "10: " #op " %" #dst " \n\t" FOP_RET #define FOP1EEX(op, dst) \ FOP1E(op, dst) _ASM_EXTABLE(10b, kvm_fastop_exception) @@ -357,7 +363,8 @@ static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)); FOP_END #define FOP2E(op, dst, src) \ - FOP_ALIGN #op " %" #src ", %" #dst " \n\t" FOP_RET + FOP_FUNC(#op "_" #dst "_" #src) \ + #op " %" #src ", %" #dst " \n\t" FOP_RET #define FASTOP2(op) \ FOP_START(op) \ @@ -395,7 +402,8 @@ static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)); FOP_END #define FOP3E(op, dst, src, src2) \ - FOP_ALIGN #op " %" #src2 ", %" #src ", %" #dst " \n\t" FOP_RET + FOP_FUNC(#op "_" #dst "_" #src "_" #src2) \ + #op " %" #src2 ", %" #src ", %" #dst " \n\t" FOP_RET /* 3-operand, word-only, src2=cl */ #define FASTOP3WCL(op) \ @@ -407,7 +415,12 @@ static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)); FOP_END /* Special case for SETcc - 1 instruction per cc */ -#define FOP_SETCC(op) ".align 4; " #op " %al; ret \n\t" +#define FOP_SETCC(op) \ + ".align 4 \n\t" \ + ".type " #op ", @function \n\t" \ + #op ": \n\t" \ + #op " %al \n\t" \ + FOP_RET asm(".global kvm_fastop_exception \n" "kvm_fastop_exception: xor %esi, %esi; ret"); From cb7390fed4c04e609a420ac0b1c07a7a781b43bf Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Fri, 22 Jan 2016 10:16:12 -0600 Subject: [PATCH 22/52] x86/kvm: Make test_cc() always inline With some configs (including allyesconfig), gcc doesn't inline test_cc(). When that happens, test_cc() doesn't create a stack frame before inserting the inline asm call instruction. This breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and can result in a bad stack trace. Force it to always be inlined so that its containing function's stack frame can be used. Suggested-by: Paolo Bonzini Signed-off-by: Josh Poimboeuf Acked-by: Paolo Bonzini Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: Gleb Natapov Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kvm@vger.kernel.org Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/20160122161612.GE20502@treble.redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kvm/emulate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index aa4d72667878..80363ebfd0a6 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -969,7 +969,7 @@ static int em_bsr_c(struct x86_emulate_ctxt *ctxt) return fastop(ctxt, em_bsr); } -static u8 test_cc(unsigned int condition, unsigned long flags) +static __always_inline u8 test_cc(unsigned int condition, unsigned long flags) { u8 rc; void (*fop)(void) = (void *)em_setcc + 4 * (condition & 0xf); From 5c1d5f283a855a5fe6b4f122054d85072b97ae4a Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:31 -0600 Subject: [PATCH 23/52] watchdog/hpwdt: Create stack frame in asminline_call() asminline_call() is a callable non-leaf function which doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create a stack frame when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: Guenter Roeck Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Wim Van Sebroeck Cc: linux-watchdog@vger.kernel.org Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/60de3cfb6f16d413bfb923036cc87fec132df735.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- drivers/watchdog/hpwdt.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c index 92443c319e59..90016db7942d 100644 --- a/drivers/watchdog/hpwdt.c +++ b/drivers/watchdog/hpwdt.c @@ -353,10 +353,10 @@ static int detect_cru_service(void) asm(".text \n\t" ".align 4 \n\t" - ".globl asminline_call \n" + ".globl asminline_call \n\t" + ".type asminline_call, @function \n\t" "asminline_call: \n\t" - "pushq %rbp \n\t" - "movq %rsp, %rbp \n\t" + FRAME_BEGIN "pushq %rax \n\t" "pushq %rbx \n\t" "pushq %rdx \n\t" @@ -386,7 +386,7 @@ asm(".text \n\t" "popq %rdx \n\t" "popq %rbx \n\t" "popq %rax \n\t" - "leave \n\t" + FRAME_END "ret \n\t" ".previous"); From 16df4ff8604881db0130f93f4b6ade759fa48e87 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:32 -0600 Subject: [PATCH 24/52] x86/locking: Create stack frame in PV unlock The assembly PV_UNLOCK function is a callable non-leaf function which doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create a stack frame when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Waiman Long Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/6685a72ddbbd0ad3694337cca0af4b4ea09f5f40.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/qspinlock_paravirt.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/include/asm/qspinlock_paravirt.h b/arch/x86/include/asm/qspinlock_paravirt.h index 9f92c180ed2f..9d55f9b6e167 100644 --- a/arch/x86/include/asm/qspinlock_paravirt.h +++ b/arch/x86/include/asm/qspinlock_paravirt.h @@ -36,8 +36,10 @@ PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath); */ asm (".pushsection .text;" ".globl " PV_UNLOCK ";" + ".type " PV_UNLOCK ", @function;" ".align 4,0x90;" PV_UNLOCK ": " + FRAME_BEGIN "push %rdx;" "mov $0x1,%eax;" "xor %edx,%edx;" @@ -45,6 +47,7 @@ asm (".pushsection .text;" "cmp $0x1,%al;" "jne .slowpath;" "pop %rdx;" + FRAME_END "ret;" ".slowpath: " "push %rsi;" @@ -52,6 +55,7 @@ asm (".pushsection .text;" "call " PV_UNLOCK_SLOWPATH ";" "pop %rsi;" "pop %rdx;" + FRAME_END "ret;" ".size " PV_UNLOCK ", .-" PV_UNLOCK ";" ".popsection"); From 3f62de5f6f369b67b7ac709e3c942c9130d2c51a Mon Sep 17 00:00:00 2001 From: Chris J Arges Date: Fri, 22 Jan 2016 15:44:38 -0600 Subject: [PATCH 25/52] x86/kvm: Add output operand in vmx_handle_external_intr inline asm Stacktool generates the following warning: stacktool: arch/x86/kvm/vmx.o: vmx_handle_external_intr()+0x67: call without frame pointer save/setup By adding the stackpointer as an output operand, this patch ensures that a stack frame is created when CONFIG_FRAME_POINTER is enabled for the inline assmebly statement. Signed-off-by: Chris J Arges Reviewed-by: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: gleb@kernel.org Cc: kvm@vger.kernel.org Cc: live-patching@vger.kernel.org Cc: pbonzini@redhat.com Link: http://lkml.kernel.org/r/1453499078-9330-3-git-send-email-chris.j.arges@canonical.com Signed-off-by: Ingo Molnar --- arch/x86/kvm/vmx.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index e2951b6edbbc..e1535225bc1d 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -8356,6 +8356,7 @@ static void vmx_complete_atomic_exit(struct vcpu_vmx *vmx) static void vmx_handle_external_intr(struct kvm_vcpu *vcpu) { u32 exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO); + register void *__sp asm(_ASM_SP); /* * If external interrupt exists, IF bit is set in rflags/eflags on the @@ -8388,8 +8389,9 @@ static void vmx_handle_external_intr(struct kvm_vcpu *vcpu) "call *%[entry]\n\t" : #ifdef CONFIG_X86_64 - [sp]"=&r"(tmp) + [sp]"=&r"(tmp), #endif + "+r"(__sp) : [entry]"r"(entry), [ss]"i"(__KERNEL_DS), From 821eae7d14f0bbf69df1cc4656c54900b2672928 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 18 Feb 2016 11:41:58 -0600 Subject: [PATCH 26/52] sched/x86: Add stack frame dependency to __preempt_schedule[_notrace]() If __preempt_schedule() or __preempt_schedule_notrace() is referenced at the beginning of a function, gcc can insert the asm inline "call ___preempt_schedule[_notrace]" instruction before setting up a stack frame, which breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and can result in bad stack traces. Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by listing the stack pointer as an output operand for the inline asm statements. Specifically this fixes the following stacktool warnings: stacktool: drivers/scsi/hpsa.o: hpsa_scsi_do_simple_cmd.constprop.106()+0x79: call without frame pointer save/setup stacktool: fs/mbcache.o: mb_cache_entry_find_first()+0x70: call without frame pointer save/setup stacktool: fs/mbcache.o: mb_cache_entry_find_first()+0x92: call without frame pointer save/setup stacktool: fs/mbcache.o: mb_cache_entry_free()+0xff: call without frame pointer save/setup stacktool: fs/mbcache.o: mb_cache_entry_free()+0xf5: call without frame pointer save/setup stacktool: fs/mbcache.o: mb_cache_entry_free()+0x11a: call without frame pointer save/setup stacktool: fs/mbcache.o: mb_cache_entry_get()+0x225: call without frame pointer save/setup stacktool: kernel/locking/percpu-rwsem.o: percpu_up_read()+0x27: call without frame pointer save/setup stacktool: kernel/profile.o: do_profile_hits.isra.5()+0x139: call without frame pointer save/setup stacktool: lib/nmi_backtrace.o: nmi_trigger_all_cpu_backtrace()+0x2b6: call without frame pointer save/setup stacktool: net/rds/ib_cm.o: rds_ib_cq_comp_handler_recv()+0x58: call without frame pointer save/setup stacktool: net/rds/ib_cm.o: rds_ib_cq_comp_handler_send()+0x58: call without frame pointer save/setup stacktool: net/rds/ib_recv.o: rds_ib_attempt_ack()+0xc1: call without frame pointer save/setup stacktool: net/rds/iw_recv.o: rds_iw_attempt_ack()+0xc1: call without frame pointer save/setup stacktool: net/rds/iw_recv.o: rds_iw_recv_cq_comp_handler()+0x55: call without frame pointer save/setup So it only adds a stack frame to 15 call sites out of ~5000 calls to ___preempt_schedule[_notrace](). All the others already had stack frames. Oddly, this change actually seems to make things faster in a lot of cases. For many smaller functions it causes the stack frame creation to get moved out of the common path and into the unlikely path. For example, here's the original cyc2ns_read_end(): ffffffff8101f8c0 : ffffffff8101f8c0: 55 push %rbp ffffffff8101f8c1: 48 89 e5 mov %rsp,%rbp ffffffff8101f8c4: 83 6f 10 01 subl $0x1,0x10(%rdi) ffffffff8101f8c8: 75 08 jne ffffffff8101f8d2 ffffffff8101f8ca: 65 48 89 3d e6 5a ff mov %rdi,%gs:0x7eff5ae6(%rip) # 153b8 ffffffff8101f8d1: 7e ffffffff8101f8d2: 65 ff 0d 77 c4 fe 7e decl %gs:0x7efec477(%rip) # bd50 <__preempt_count> ffffffff8101f8d9: 74 02 je ffffffff8101f8dd ffffffff8101f8db: 5d pop %rbp ffffffff8101f8dc: c3 retq ffffffff8101f8dd: e8 1e 37 fe ff callq ffffffff81003000 <___preempt_schedule> ffffffff8101f8e2: 5d pop %rbp ffffffff8101f8e3: c3 retq ffffffff8101f8e4: 66 66 66 2e 0f 1f 84 data16 data16 nopw %cs:0x0(%rax,%rax,1) ffffffff8101f8eb: 00 00 00 00 00 And here's the same function with the patch: ffffffff8101f8c0 : ffffffff8101f8c0: 83 6f 10 01 subl $0x1,0x10(%rdi) ffffffff8101f8c4: 75 08 jne ffffffff8101f8ce ffffffff8101f8c6: 65 48 89 3d ea 5a ff mov %rdi,%gs:0x7eff5aea(%rip) # 153b8 ffffffff8101f8cd: 7e ffffffff8101f8ce: 65 ff 0d 7b c4 fe 7e decl %gs:0x7efec47b(%rip) # bd50 <__preempt_count> ffffffff8101f8d5: 74 01 je ffffffff8101f8d8 ffffffff8101f8d7: c3 retq ffffffff8101f8d8: 55 push %rbp ffffffff8101f8d9: 48 89 e5 mov %rsp,%rbp ffffffff8101f8dc: e8 1f 37 fe ff callq ffffffff81003000 <___preempt_schedule> ffffffff8101f8e1: 5d pop %rbp ffffffff8101f8e2: c3 retq ffffffff8101f8e3: 66 66 66 66 2e 0f 1f data16 data16 data16 nopw %cs:0x0(%rax,%rax,1) ffffffff8101f8ea: 84 00 00 00 00 00 Notice that it moved the frame pointer setup code to the unlikely ___preempt_schedule() call path. Going through a sampling of the differences in the asm, that's the most common change I see. Otherwise it has no real effect on callers which already have stack frames (though it does result in the reordering of some 'mov's). Reported-by: Jiri Slaby Tested-by: Jiri Slaby Signed-off-by: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/20160218174158.GA28230@treble.redhat.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/preempt.h | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h index 01bcde84d3e4..d397deb58146 100644 --- a/arch/x86/include/asm/preempt.h +++ b/arch/x86/include/asm/preempt.h @@ -94,10 +94,19 @@ static __always_inline bool should_resched(int preempt_offset) #ifdef CONFIG_PREEMPT extern asmlinkage void ___preempt_schedule(void); -# define __preempt_schedule() asm ("call ___preempt_schedule") +# define __preempt_schedule() \ +({ \ + register void *__sp asm(_ASM_SP); \ + asm volatile ("call ___preempt_schedule" : "+r"(__sp)); \ +}) + extern asmlinkage void preempt_schedule(void); extern asmlinkage void ___preempt_schedule_notrace(void); -# define __preempt_schedule_notrace() asm ("call ___preempt_schedule_notrace") +# define __preempt_schedule_notrace() \ +({ \ + register void *__sp asm(_ASM_SP); \ + asm volatile ("call ___preempt_schedule_notrace" : "+r"(__sp)); \ +}) extern asmlinkage void preempt_schedule_notrace(void); #endif From 1923f3d02768bd904dfe5607f3f93c3008b8db61 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 25 Feb 2016 08:27:27 +0100 Subject: [PATCH 27/52] watchdog/hpwdt: Fix build on certain configs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fix the following build failure: drivers/watchdog/hpwdt.c:359:5: error: expected ‘)’ before ‘FRAME_BEGIN’ which occurs because hpwdt.c relied on indirect inclusion to get asm/frame.h definitions - but some (mostly randconfig) configs did not provide that. Include explicitly. Cc: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: Guenter Roeck Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Wim Van Sebroeck Cc: linux-watchdog@vger.kernel.org Cc: live-patching@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- drivers/watchdog/hpwdt.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c index 90016db7942d..8fc284cdce4e 100644 --- a/drivers/watchdog/hpwdt.c +++ b/drivers/watchdog/hpwdt.c @@ -37,6 +37,7 @@ #include #endif /* CONFIG_HPWDT_NMI_DECODING */ #include +#include #define HPWDT_VERSION "1.3.3" #define SECS_TO_TICKS(secs) ((secs) * 1000 / 128) From c0dd671686b2229e888ede77682ab0633b2a0dd7 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:34 -0600 Subject: [PATCH 28/52] objtool: Mark non-standard object files and directories Code which runs outside the kernel's normal mode of operation often does unusual things which can cause a static analysis tool like objtool to emit false positive warnings: - boot image - vdso image - relocation - realmode - efi - head - purgatory - modpost Set OBJECT_FILES_NON_STANDARD for their related files and directories, which will tell objtool to skip checking them. It's ok to skip them because they don't affect runtime stack traces. Also skip the following code which does the right thing with respect to frame pointers, but is too "special" to be validated by a tool: - entry - mcount Also skip the test_nx module because it modifies its exception handling table at runtime, which objtool can't understand. Fortunately it's just a test module so it doesn't matter much. Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but it might eventually be useful for other tools. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/boot/Makefile | 3 ++- arch/x86/boot/compressed/Makefile | 3 ++- arch/x86/entry/Makefile | 4 ++++ arch/x86/entry/vdso/Makefile | 6 ++++-- arch/x86/kernel/Makefile | 11 ++++++++--- arch/x86/platform/efi/Makefile | 2 ++ arch/x86/purgatory/Makefile | 2 ++ arch/x86/realmode/Makefile | 4 +++- arch/x86/realmode/rm/Makefile | 3 ++- drivers/firmware/efi/libstub/Makefile | 1 + scripts/mod/Makefile | 2 ++ 11 files changed, 32 insertions(+), 9 deletions(-) diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile index bbe1a62efc02..0bf6749522d9 100644 --- a/arch/x86/boot/Makefile +++ b/arch/x86/boot/Makefile @@ -9,7 +9,8 @@ # Changed by many, many contributors over the years. # -KASAN_SANITIZE := n +KASAN_SANITIZE := n +OBJECT_FILES_NON_STANDARD := y # If you want to preset the SVGA mode, uncomment the next line and # set SVGA_MODE to whatever number you want. diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index f9ce75d80101..5e1d26e09407 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -16,7 +16,8 @@ # (see scripts/Makefile.lib size_append) # compressed vmlinux.bin.all + u32 size of vmlinux.bin.all -KASAN_SANITIZE := n +KASAN_SANITIZE := n +OBJECT_FILES_NON_STANDARD := y targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \ vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4 diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile index bd55dedd7614..fe91c25092da 100644 --- a/arch/x86/entry/Makefile +++ b/arch/x86/entry/Makefile @@ -1,6 +1,10 @@ # # Makefile for the x86 low level entry code # + +OBJECT_FILES_NON_STANDARD_entry_$(BITS).o := y +OBJECT_FILES_NON_STANDARD_entry_64_compat.o := y + obj-y := entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o obj-y += common.o diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index c854541d93ff..f9fb859c98b9 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -3,8 +3,9 @@ # KBUILD_CFLAGS += $(DISABLE_LTO) -KASAN_SANITIZE := n -UBSAN_SANITIZE := n +KASAN_SANITIZE := n +UBSAN_SANITIZE := n +OBJECT_FILES_NON_STANDARD := y VDSO64-$(CONFIG_X86_64) := y VDSOX32-$(CONFIG_X86_X32_ABI) := y @@ -16,6 +17,7 @@ vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o # files to link into kernel obj-y += vma.o +OBJECT_FILES_NON_STANDARD_vma.o := n # vDSO images to build vdso_img-$(VDSO64-y) += 64 diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index b1b78ffe01d0..d5fb0871aba3 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -16,9 +16,14 @@ CFLAGS_REMOVE_ftrace.o = -pg CFLAGS_REMOVE_early_printk.o = -pg endif -KASAN_SANITIZE_head$(BITS).o := n -KASAN_SANITIZE_dumpstack.o := n -KASAN_SANITIZE_dumpstack_$(BITS).o := n +KASAN_SANITIZE_head$(BITS).o := n +KASAN_SANITIZE_dumpstack.o := n +KASAN_SANITIZE_dumpstack_$(BITS).o := n + +OBJECT_FILES_NON_STANDARD_head_$(BITS).o := y +OBJECT_FILES_NON_STANDARD_relocate_kernel_$(BITS).o := y +OBJECT_FILES_NON_STANDARD_mcount_$(BITS).o := y +OBJECT_FILES_NON_STANDARD_test_nx.o := y CFLAGS_irq.o := -I$(src)/../include/asm/trace diff --git a/arch/x86/platform/efi/Makefile b/arch/x86/platform/efi/Makefile index 2846aaab5103..066619b0700c 100644 --- a/arch/x86/platform/efi/Makefile +++ b/arch/x86/platform/efi/Makefile @@ -1,3 +1,5 @@ +OBJECT_FILES_NON_STANDARD_efi_thunk_$(BITS).o := y + obj-$(CONFIG_EFI) += quirks.o efi.o efi_$(BITS).o efi_stub_$(BITS).o obj-$(CONFIG_ACPI_BGRT) += efi-bgrt.o obj-$(CONFIG_EARLY_PRINTK_EFI) += early_printk.o diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile index 2c835e356349..92e3e1d84c1d 100644 --- a/arch/x86/purgatory/Makefile +++ b/arch/x86/purgatory/Makefile @@ -1,3 +1,5 @@ +OBJECT_FILES_NON_STANDARD := y + purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string.o targets += $(purgatory-y) diff --git a/arch/x86/realmode/Makefile b/arch/x86/realmode/Makefile index e02c2c6c56a5..682c895753d9 100644 --- a/arch/x86/realmode/Makefile +++ b/arch/x86/realmode/Makefile @@ -6,7 +6,9 @@ # for more details. # # -KASAN_SANITIZE := n +KASAN_SANITIZE := n +OBJECT_FILES_NON_STANDARD := y + subdir- := rm obj-y += init.o diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile index 3e75fcf6b836..053abe7b0ef7 100644 --- a/arch/x86/realmode/rm/Makefile +++ b/arch/x86/realmode/rm/Makefile @@ -6,7 +6,8 @@ # for more details. # # -KASAN_SANITIZE := n +KASAN_SANITIZE := n +OBJECT_FILES_NON_STANDARD := y always := realmode.bin realmode.relocs diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index aaf9c0bab42e..68fa977b2c1b 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -23,6 +23,7 @@ KBUILD_CFLAGS := $(cflags-y) -DDISABLE_BRANCH_PROFILING \ GCOV_PROFILE := n KASAN_SANITIZE := n UBSAN_SANITIZE := n +OBJECT_FILES_NON_STANDARD := y lib-y := efi-stub-helper.o diff --git a/scripts/mod/Makefile b/scripts/mod/Makefile index c11212ff3510..19d9bcadc0cc 100644 --- a/scripts/mod/Makefile +++ b/scripts/mod/Makefile @@ -1,3 +1,5 @@ +OBJECT_FILES_NON_STANDARD := y + hostprogs-y := modpost mk_elfconfig always := $(hostprogs-y) empty.o From 9a99417acbad99ba6c6a9389b45a53a4d002bb7e Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:35 -0600 Subject: [PATCH 29/52] objtool: Add STACK_FRAME_NON_STANDARD() macro Add a new macro, STACK_FRAME_NON_STANDARD(), which is used to denote a function which does something unusual related to its stack frame. Use of the macro prevents objtool from emitting a false positive warning. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/34487a17b23dba43c50941599d47054a9584b219.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/vmlinux.lds.S | 5 ++++- include/linux/frame.h | 23 +++++++++++++++++++++++ 2 files changed, 27 insertions(+), 1 deletion(-) create mode 100644 include/linux/frame.h diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 92dc211c11db..13fa0ad62df8 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -343,7 +343,10 @@ SECTIONS /* Sections to be discarded */ DISCARDS - /DISCARD/ : { *(.eh_frame) } + /DISCARD/ : { + *(.eh_frame) + *(__func_stack_frame_non_standard) + } } diff --git a/include/linux/frame.h b/include/linux/frame.h new file mode 100644 index 000000000000..e6baaba3f1ae --- /dev/null +++ b/include/linux/frame.h @@ -0,0 +1,23 @@ +#ifndef _LINUX_FRAME_H +#define _LINUX_FRAME_H + +#ifdef CONFIG_STACK_VALIDATION +/* + * This macro marks the given function's stack frame as "non-standard", which + * tells objtool to ignore the function when doing stack metadata validation. + * It should only be used in special cases where you're 100% sure it won't + * affect the reliability of frame pointers and kernel stack traces. + * + * For more information, see tools/objtool/Documentation/stack-validation.txt. + */ +#define STACK_FRAME_NON_STANDARD(func) \ + static void __used __section(__func_stack_frame_non_standard) \ + *__func_stack_frame_non_standard_##func = func + +#else /* !CONFIG_STACK_VALIDATION */ + +#define STACK_FRAME_NON_STANDARD(func) + +#endif /* CONFIG_STACK_VALIDATION */ + +#endif /* _LINUX_FRAME_H */ From 983bb6d254c77aaec581473e11c2eb859294f1f2 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:36 -0600 Subject: [PATCH 30/52] x86/xen: Mark xen_cpuid() stack frame as non-standard objtool reports the following false positive warning: arch/x86/xen/enlighten.o: warning: objtool: xen_cpuid()+0x41: can't find jump dest instruction at .text+0x108 The warning is due to xen_cpuid()'s use of XEN_EMULATE_PREFIX to insert some fake instructions which objtool doesn't know how to decode. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Chris J Arges Cc: David Vrabel Cc: Jiri Slaby Cc: Konrad Rzeszutek Wilk Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/bb88399840406629e3417831dc371ecd2842e2a6.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/xen/enlighten.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index d09e4c9d7cc5..5c45a69ffe84 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -32,6 +32,7 @@ #include #include #include +#include #ifdef CONFIG_KEXEC_CORE #include @@ -351,8 +352,8 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, *cx &= maskecx; *cx |= setecx; *dx &= maskedx; - } +STACK_FRAME_NON_STANDARD(xen_cpuid); /* XEN_EMULATE_PREFIX */ static bool __init xen_check_mwait(void) { From 39853cc0cdcf1b11f00f7f81e2f515a4d68ed209 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:37 -0600 Subject: [PATCH 31/52] bpf: Mark __bpf_prog_run() stack frame as non-standard objtool reports the following false positive warnings: kernel/bpf/core.o: warning: objtool: __bpf_prog_run()+0x5c: sibling call from callable instruction with changed frame pointer kernel/bpf/core.o: warning: objtool: __bpf_prog_run()+0x60: function has unreachable instruction kernel/bpf/core.o: warning: objtool: __bpf_prog_run()+0x64: function has unreachable instruction [...] It's confused by the following dynamic jump instruction in __bpf_prog_run():: jmp *(%r12,%rax,8) which corresponds to the following line in the C code: goto *jumptable[insn->code]; There's no way for objtool to deterministically find all possible branch targets for a dynamic jump, so it can't verify this code. In this case the jumps all stay within the function, and there's nothing unusual going on related to the stack, so we can whitelist the function. Signed-off-by: Josh Poimboeuf Acked-by: Daniel Borkmann Acked-by: Alexei Starovoitov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/b90e6bf3fdbfb5c4cc1b164b965502e53cf48935.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- kernel/bpf/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 972d9a8e4ac4..be0abf669ced 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -27,6 +27,7 @@ #include #include #include +#include #include @@ -649,6 +650,7 @@ static unsigned int __bpf_prog_run(void *ctx, const struct bpf_insn *insn) WARN_RATELIMIT(1, "unknown opcode %02x\n", insn->code); return 0; } +STACK_FRAME_NON_STANDARD(__bpf_prog_run); /* jump table */ bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp) From 8e05e96ac949c80704d0a38420bf60dcf18c938f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:38 -0600 Subject: [PATCH 32/52] sched: Mark __schedule() stack frame as non-standard objtool reports the following warnings for __schedule(): kernel/sched/core.o: warning: objtool:__schedule()+0x3c0: duplicate frame pointer save kernel/sched/core.o: warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer kernel/sched/core.o: warning: objtool:__schedule()+0x40a: call without frame pointer save/setup kernel/sched/core.o: warning: objtool:__schedule()+0x7fd: frame pointer state mismatch kernel/sched/core.o: warning: objtool:__schedule()+0x421: frame pointer state mismatch Basically it's confused by two unusual attributes of the switch_to() macro: 1. It saves prev's frame pointer to the old stack and restores next's frame pointer from the new stack. 2. For new tasks it jumps directly to ret_from_fork. Eventually it would probably be a good idea to clean up the ret_from_fork hack so that new tasks are created with a valid initial stack, as suggested by Andy: https://lkml.kernel.org/r/CALCETrWsqCw4L1qKO9j9L5F+4ED4viuLQTFc=n1pKBZfFPQUFg@mail.gmail.com Then __schedule() could return normally into the new code and objtool hopefully wouldn't have a problem anymore. In the meantime, mark its stack frame as non-standard so we can have a baseline with no objtool warnings. The marker also serves as a reminder that this code could be improved a bit. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/91190e324ebd7fcd01748d508d0dfd4693e84d91.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 9503d590e5ef..641043dfc773 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -74,6 +74,7 @@ #include #include #include +#include #include #include @@ -3288,6 +3289,7 @@ static void __sched notrace __schedule(bool preempt) balance_callback(rq); } +STACK_FRAME_NON_STANDARD(__schedule); /* switch_to() */ static inline void sched_submit_work(struct task_struct *tsk) { From 049369487e2068294b61cee19233be0ffac7d243 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:39 -0600 Subject: [PATCH 33/52] sched: Always inline context_switch() When CONFIG_GCOV is enabled, gcc decides to put context_switch() out-of-line, which is inconsistent with its normal behavior. It also causes an objtool warning because __schedule() no longer inlines context_switch(), so the "STACK_FRAME_NON_STANDARD(__schedule)" statement loses its effect. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/d62aee926b6e303394e34a06999a964dc2773cf6.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 641043dfc773..bb0daabe0ffe 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2763,7 +2763,7 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev) /* * context_switch - switch to the new MM and the new thread's register state. */ -static inline struct rq * +static __always_inline struct rq * context_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) { From 87aaff2ae09036cf699fde20dfd52ce7d3c8eabe Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:40 -0600 Subject: [PATCH 34/52] x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard objtool reports the following warning for kretprobe_trampoline(): arch/x86/kernel/kprobes/core.o: warning: objtool: kretprobe_trampoline()+0x20: call without frame pointer save/setup kretprobes are a special case where the stack is intentionally wrong. The return address isn't known at the beginning of the trampoline, so the stack frame can't be set up properly before it calls trampoline_handler(). Because kretprobe handlers don't sleep, the frame pointer doesn't *have* to be accurate in the trampoline. So it's ok to tell objtool to ignore it. This results in no actual changes to the generated code. Signed-off-by: Josh Poimboeuf Cc: Ananth N Mavinakayanahalli Cc: Andrew Morton Cc: Andy Lutomirski Cc: Anil S Keshavamurthy Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: David S. Miller Cc: Jiri Slaby Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/7eaf37de52456ff822ffc86b928edb5d48a40ef1.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/kprobes/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 48acaac35bd2..ae703acb85c1 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -49,6 +49,7 @@ #include #include #include +#include #include #include @@ -703,6 +704,7 @@ asm( ".size kretprobe_trampoline, .-kretprobe_trampoline\n" ); NOKPROBE_SYMBOL(kretprobe_trampoline); +STACK_FRAME_NON_STANDARD(kretprobe_trampoline); /* * Called from kretprobe_trampoline From 442f04c34a1a467759d024a1d2c1df0f744dcb06 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:41 -0600 Subject: [PATCH 35/52] objtool: Add tool to perform compile-time stack metadata validation This adds a host tool named objtool which has a "check" subcommand which analyzes .o files to ensure the validity of stack metadata. It enforces a set of rules on asm code and C inline assembly code so that stack traces can be reliable. For each function, it recursively follows all possible code paths and validates the correct frame pointer state at each instruction. It also follows code paths involving kernel special sections, like .altinstructions, __jump_table, and __ex_table, which can add alternative execution paths to a given instruction (or set of instructions). Similarly, it knows how to follow switch statements, for which gcc sometimes uses jump tables. Here are some of the benefits of validating stack metadata: a) More reliable stack traces for frame pointer enabled kernels Frame pointers are used for debugging purposes. They allow runtime code and debug tools to be able to walk the stack to determine the chain of function call sites that led to the currently executing code. For some architectures, frame pointers are enabled by CONFIG_FRAME_POINTER. For some other architectures they may be required by the ABI (sometimes referred to as "backchain pointers"). For C code, gcc automatically generates instructions for setting up frame pointers when the -fno-omit-frame-pointer option is used. But for asm code, the frame setup instructions have to be written by hand, which most people don't do. So the end result is that CONFIG_FRAME_POINTER is honored for C code but not for most asm code. For stack traces based on frame pointers to be reliable, all functions which call other functions must first create a stack frame and update the frame pointer. If a first function doesn't properly create a stack frame before calling a second function, the *caller* of the first function will be skipped on the stack trace. For example, consider the following example backtrace with frame pointers enabled: [] dump_stack+0x4b/0x63 [] cmdline_proc_show+0x12/0x30 [] seq_read+0x108/0x3e0 [] proc_reg_read+0x42/0x70 [] __vfs_read+0x37/0x100 [] vfs_read+0x86/0x130 [] SyS_read+0x58/0xd0 [] entry_SYSCALL_64_fastpath+0x12/0x76 It correctly shows that the caller of cmdline_proc_show() is seq_read(). If we remove the frame pointer logic from cmdline_proc_show() by replacing the frame pointer related instructions with nops, here's what it looks like instead: [] dump_stack+0x4b/0x63 [] cmdline_proc_show+0x12/0x30 [] proc_reg_read+0x42/0x70 [] __vfs_read+0x37/0x100 [] vfs_read+0x86/0x130 [] SyS_read+0x58/0xd0 [] entry_SYSCALL_64_fastpath+0x12/0x76 Notice that cmdline_proc_show()'s caller, seq_read(), has been skipped. Instead the stack trace seems to show that cmdline_proc_show() was called by proc_reg_read(). The benefit of "objtool check" here is that because it ensures that *all* functions honor CONFIG_FRAME_POINTER, no functions will ever[*] be skipped on a stack trace. [*] unless an interrupt or exception has occurred at the very beginning of a function before the stack frame has been created, or at the very end of the function after the stack frame has been destroyed. This is an inherent limitation of frame pointers. b) 100% reliable stack traces for DWARF enabled kernels This is not yet implemented. For more details about what is planned, see tools/objtool/Documentation/stack-validation.txt. c) Higher live patching compatibility rate This is not yet implemented. For more details about what is planned, see tools/objtool/Documentation/stack-validation.txt. To achieve the validation, "objtool check" enforces the following rules: 1. Each callable function must be annotated as such with the ELF function type. In asm code, this is typically done using the ENTRY/ENDPROC macros. If objtool finds a return instruction outside of a function, it flags an error since that usually indicates callable code which should be annotated accordingly. This rule is needed so that objtool can properly identify each callable function in order to analyze its stack metadata. 2. Conversely, each section of code which is *not* callable should *not* be annotated as an ELF function. The ENDPROC macro shouldn't be used in this case. This rule is needed so that objtool can ignore non-callable code. Such code doesn't have to follow any of the other rules. 3. Each callable function which calls another function must have the correct frame pointer logic, if required by CONFIG_FRAME_POINTER or the architecture's back chain rules. This can by done in asm code with the FRAME_BEGIN/FRAME_END macros. This rule ensures that frame pointer based stack traces will work as designed. If function A doesn't create a stack frame before calling function B, the _caller_ of function A will be skipped on the stack trace. 4. Dynamic jumps and jumps to undefined symbols are only allowed if: a) the jump is part of a switch statement; or b) the jump matches sibling call semantics and the frame pointer has the same value it had on function entry. This rule is needed so that objtool can reliably analyze all of a function's code paths. If a function jumps to code in another file, and it's not a sibling call, objtool has no way to follow the jump because it only analyzes a single file at a time. 5. A callable function may not execute kernel entry/exit instructions. The only code which needs such instructions is kernel entry code, which shouldn't be be in callable functions anyway. This rule is just a sanity check to ensure that callable functions return normally. It currently only supports x86_64. I tried to make the code generic so that support for other architectures can hopefully be plugged in relatively easily. On my Lenovo laptop with a i7-4810MQ 4-core/8-thread CPU, building the kernel with objtool checking every .o file adds about three seconds of total build time. It hasn't been optimized for performance yet, so there are probably some opportunities for better build performance. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/f3efb173de43bd067b060de73f856567c0fa1174.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- MAINTAINERS | 5 + tools/Makefile | 14 +- tools/objtool/.gitignore | 2 + tools/objtool/Build | 13 + .../Documentation/stack-validation.txt | 342 ++++++ tools/objtool/Makefile | 60 + tools/objtool/arch.h | 44 + tools/objtool/arch/x86/Build | 12 + tools/objtool/arch/x86/decode.c | 172 +++ .../arch/x86/insn/gen-insn-attr-x86.awk | 387 ++++++ tools/objtool/arch/x86/insn/inat.c | 97 ++ tools/objtool/arch/x86/insn/inat.h | 221 ++++ tools/objtool/arch/x86/insn/inat_types.h | 29 + tools/objtool/arch/x86/insn/insn.c | 594 +++++++++ tools/objtool/arch/x86/insn/insn.h | 201 ++++ .../objtool/arch/x86/insn/x86-opcode-map.txt | 984 +++++++++++++++ tools/objtool/builtin-check.c | 1072 +++++++++++++++++ tools/objtool/builtin.h | 22 + tools/objtool/elf.c | 403 +++++++ tools/objtool/elf.h | 79 ++ tools/objtool/objtool.c | 136 +++ tools/objtool/special.c | 193 +++ tools/objtool/special.h | 42 + tools/objtool/warn.h | 60 + 24 files changed, 5178 insertions(+), 6 deletions(-) create mode 100644 tools/objtool/.gitignore create mode 100644 tools/objtool/Build create mode 100644 tools/objtool/Documentation/stack-validation.txt create mode 100644 tools/objtool/Makefile create mode 100644 tools/objtool/arch.h create mode 100644 tools/objtool/arch/x86/Build create mode 100644 tools/objtool/arch/x86/decode.c create mode 100644 tools/objtool/arch/x86/insn/gen-insn-attr-x86.awk create mode 100644 tools/objtool/arch/x86/insn/inat.c create mode 100644 tools/objtool/arch/x86/insn/inat.h create mode 100644 tools/objtool/arch/x86/insn/inat_types.h create mode 100644 tools/objtool/arch/x86/insn/insn.c create mode 100644 tools/objtool/arch/x86/insn/insn.h create mode 100644 tools/objtool/arch/x86/insn/x86-opcode-map.txt create mode 100644 tools/objtool/builtin-check.c create mode 100644 tools/objtool/builtin.h create mode 100644 tools/objtool/elf.c create mode 100644 tools/objtool/elf.h create mode 100644 tools/objtool/objtool.c create mode 100644 tools/objtool/special.c create mode 100644 tools/objtool/special.h create mode 100644 tools/objtool/warn.h diff --git a/MAINTAINERS b/MAINTAINERS index 2fa3303ea625..545daaf4b91c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7778,6 +7778,11 @@ L: alsa-devel@alsa-project.org (moderated for non-subscribers) S: Maintained F: sound/soc/codecs/tfa9879* +OBJTOOL +M: Josh Poimboeuf +S: Supported +F: tools/objtool/ + OMAP SUPPORT M: Tony Lindgren L: linux-omap@vger.kernel.org diff --git a/tools/Makefile b/tools/Makefile index 6339f6ac3ccb..cc2a37d975d6 100644 --- a/tools/Makefile +++ b/tools/Makefile @@ -20,6 +20,7 @@ help: @echo ' perf - Linux performance measurement and analysis tool' @echo ' selftests - various kernel selftests' @echo ' spi - spi tools' + @echo ' objtool - an ELF object analysis tool' @echo ' tmon - thermal monitoring and tuning tool' @echo ' turbostat - Intel CPU idle stats and freq reporting tool' @echo ' usb - USB testing tools' @@ -53,7 +54,7 @@ acpi: FORCE cpupower: FORCE $(call descend,power/$@) -cgroup firewire hv guest spi usb virtio vm net iio: FORCE +cgroup firewire hv guest spi usb virtio vm net iio objtool: FORCE $(call descend,$@) liblockdep: FORCE @@ -85,7 +86,7 @@ freefall: FORCE all: acpi cgroup cpupower hv firewire lguest \ perf selftests turbostat usb \ virtio vm net x86_energy_perf_policy \ - tmon freefall + tmon freefall objtool acpi_install: $(call descend,power/$(@:_install=),install) @@ -93,7 +94,7 @@ acpi_install: cpupower_install: $(call descend,power/$(@:_install=),install) -cgroup_install firewire_install hv_install lguest_install perf_install usb_install virtio_install vm_install net_install: +cgroup_install firewire_install hv_install lguest_install perf_install usb_install virtio_install vm_install net_install objtool_install: $(call descend,$(@:_install=),install) selftests_install: @@ -111,7 +112,7 @@ freefall_install: install: acpi_install cgroup_install cpupower_install hv_install firewire_install lguest_install \ perf_install selftests_install turbostat_install usb_install \ virtio_install vm_install net_install x86_energy_perf_policy_install \ - tmon_install freefall_install + tmon_install freefall_install objtool_install acpi_clean: $(call descend,power/acpi,clean) @@ -119,7 +120,7 @@ acpi_clean: cpupower_clean: $(call descend,power/cpupower,clean) -cgroup_clean hv_clean firewire_clean lguest_clean spi_clean usb_clean virtio_clean vm_clean net_clean iio_clean: +cgroup_clean hv_clean firewire_clean lguest_clean spi_clean usb_clean virtio_clean vm_clean net_clean iio_clean objtool_clean: $(call descend,$(@:_clean=),clean) liblockdep_clean: @@ -155,6 +156,7 @@ build_clean: clean: acpi_clean cgroup_clean cpupower_clean hv_clean firewire_clean lguest_clean \ perf_clean selftests_clean turbostat_clean spi_clean usb_clean virtio_clean \ vm_clean net_clean iio_clean x86_energy_perf_policy_clean tmon_clean \ - freefall_clean build_clean libbpf_clean libsubcmd_clean liblockdep_clean + freefall_clean build_clean libbpf_clean libsubcmd_clean liblockdep_clean \ + objtool_clean .PHONY: FORCE diff --git a/tools/objtool/.gitignore b/tools/objtool/.gitignore new file mode 100644 index 000000000000..a0b3128bb31f --- /dev/null +++ b/tools/objtool/.gitignore @@ -0,0 +1,2 @@ +arch/x86/insn/inat-tables.c +objtool diff --git a/tools/objtool/Build b/tools/objtool/Build new file mode 100644 index 000000000000..0e89258a3541 --- /dev/null +++ b/tools/objtool/Build @@ -0,0 +1,13 @@ +objtool-y += arch/$(ARCH)/ +objtool-y += builtin-check.o +objtool-y += elf.o +objtool-y += special.o +objtool-y += objtool.o + +objtool-y += libstring.o + +CFLAGS += -I$(srctree)/tools/lib + +$(OUTPUT)libstring.o: ../lib/string.c FORCE + $(call rule_mkdir) + $(call if_changed_dep,cc_o_c) diff --git a/tools/objtool/Documentation/stack-validation.txt b/tools/objtool/Documentation/stack-validation.txt new file mode 100644 index 000000000000..5a95896105bc --- /dev/null +++ b/tools/objtool/Documentation/stack-validation.txt @@ -0,0 +1,342 @@ +Compile-time stack metadata validation +====================================== + + +Overview +-------- + +The kernel CONFIG_STACK_VALIDATION option enables a host tool named +objtool which runs at compile time. It has a "check" subcommand which +analyzes every .o file and ensures the validity of its stack metadata. +It enforces a set of rules on asm code and C inline assembly code so +that stack traces can be reliable. + +Currently it only checks frame pointer usage, but there are plans to add +CFI validation for C files and CFI generation for asm files. + +For each function, it recursively follows all possible code paths and +validates the correct frame pointer state at each instruction. + +It also follows code paths involving special sections, like +.altinstructions, __jump_table, and __ex_table, which can add +alternative execution paths to a given instruction (or set of +instructions). Similarly, it knows how to follow switch statements, for +which gcc sometimes uses jump tables. + + +Why do we need stack metadata validation? +----------------------------------------- + +Here are some of the benefits of validating stack metadata: + +a) More reliable stack traces for frame pointer enabled kernels + + Frame pointers are used for debugging purposes. They allow runtime + code and debug tools to be able to walk the stack to determine the + chain of function call sites that led to the currently executing + code. + + For some architectures, frame pointers are enabled by + CONFIG_FRAME_POINTER. For some other architectures they may be + required by the ABI (sometimes referred to as "backchain pointers"). + + For C code, gcc automatically generates instructions for setting up + frame pointers when the -fno-omit-frame-pointer option is used. + + But for asm code, the frame setup instructions have to be written by + hand, which most people don't do. So the end result is that + CONFIG_FRAME_POINTER is honored for C code but not for most asm code. + + For stack traces based on frame pointers to be reliable, all + functions which call other functions must first create a stack frame + and update the frame pointer. If a first function doesn't properly + create a stack frame before calling a second function, the *caller* + of the first function will be skipped on the stack trace. + + For example, consider the following example backtrace with frame + pointers enabled: + + [] dump_stack+0x4b/0x63 + [] cmdline_proc_show+0x12/0x30 + [] seq_read+0x108/0x3e0 + [] proc_reg_read+0x42/0x70 + [] __vfs_read+0x37/0x100 + [] vfs_read+0x86/0x130 + [] SyS_read+0x58/0xd0 + [] entry_SYSCALL_64_fastpath+0x12/0x76 + + It correctly shows that the caller of cmdline_proc_show() is + seq_read(). + + If we remove the frame pointer logic from cmdline_proc_show() by + replacing the frame pointer related instructions with nops, here's + what it looks like instead: + + [] dump_stack+0x4b/0x63 + [] cmdline_proc_show+0x12/0x30 + [] proc_reg_read+0x42/0x70 + [] __vfs_read+0x37/0x100 + [] vfs_read+0x86/0x130 + [] SyS_read+0x58/0xd0 + [] entry_SYSCALL_64_fastpath+0x12/0x76 + + Notice that cmdline_proc_show()'s caller, seq_read(), has been + skipped. Instead the stack trace seems to show that + cmdline_proc_show() was called by proc_reg_read(). + + The benefit of objtool here is that because it ensures that *all* + functions honor CONFIG_FRAME_POINTER, no functions will ever[*] be + skipped on a stack trace. + + [*] unless an interrupt or exception has occurred at the very + beginning of a function before the stack frame has been created, + or at the very end of the function after the stack frame has been + destroyed. This is an inherent limitation of frame pointers. + +b) 100% reliable stack traces for DWARF enabled kernels + + (NOTE: This is not yet implemented) + + As an alternative to frame pointers, DWARF Call Frame Information + (CFI) metadata can be used to walk the stack. Unlike frame pointers, + CFI metadata is out of band. So it doesn't affect runtime + performance and it can be reliable even when interrupts or exceptions + are involved. + + For C code, gcc automatically generates DWARF CFI metadata. But for + asm code, generating CFI is a tedious manual approach which requires + manually placed .cfi assembler macros to be scattered throughout the + code. It's clumsy and very easy to get wrong, and it makes the real + code harder to read. + + Stacktool will improve this situation in several ways. For code + which already has CFI annotations, it will validate them. For code + which doesn't have CFI annotations, it will generate them. So an + architecture can opt to strip out all the manual .cfi annotations + from their asm code and have objtool generate them instead. + + We might also add a runtime stack validation debug option where we + periodically walk the stack from schedule() and/or an NMI to ensure + that the stack metadata is sane and that we reach the bottom of the + stack. + + So the benefit of objtool here will be that external tooling should + always show perfect stack traces. And the same will be true for + kernel warning/oops traces if the architecture has a runtime DWARF + unwinder. + +c) Higher live patching compatibility rate + + (NOTE: This is not yet implemented) + + Currently with CONFIG_LIVEPATCH there's a basic live patching + framework which is safe for roughly 85-90% of "security" fixes. But + patches can't have complex features like function dependency or + prototype changes, or data structure changes. + + There's a strong need to support patches which have the more complex + features so that the patch compatibility rate for security fixes can + eventually approach something resembling 100%. To achieve that, a + "consistency model" is needed, which allows tasks to be safely + transitioned from an unpatched state to a patched state. + + One of the key requirements of the currently proposed livepatch + consistency model [*] is that it needs to walk the stack of each + sleeping task to determine if it can be transitioned to the patched + state. If objtool can ensure that stack traces are reliable, this + consistency model can be used and the live patching compatibility + rate can be improved significantly. + + [*] https://lkml.kernel.org/r/cover.1423499826.git.jpoimboe@redhat.com + + +Rules +----- + +To achieve the validation, objtool enforces the following rules: + +1. Each callable function must be annotated as such with the ELF + function type. In asm code, this is typically done using the + ENTRY/ENDPROC macros. If objtool finds a return instruction + outside of a function, it flags an error since that usually indicates + callable code which should be annotated accordingly. + + This rule is needed so that objtool can properly identify each + callable function in order to analyze its stack metadata. + +2. Conversely, each section of code which is *not* callable should *not* + be annotated as an ELF function. The ENDPROC macro shouldn't be used + in this case. + + This rule is needed so that objtool can ignore non-callable code. + Such code doesn't have to follow any of the other rules. + +3. Each callable function which calls another function must have the + correct frame pointer logic, if required by CONFIG_FRAME_POINTER or + the architecture's back chain rules. This can by done in asm code + with the FRAME_BEGIN/FRAME_END macros. + + This rule ensures that frame pointer based stack traces will work as + designed. If function A doesn't create a stack frame before calling + function B, the _caller_ of function A will be skipped on the stack + trace. + +4. Dynamic jumps and jumps to undefined symbols are only allowed if: + + a) the jump is part of a switch statement; or + + b) the jump matches sibling call semantics and the frame pointer has + the same value it had on function entry. + + This rule is needed so that objtool can reliably analyze all of a + function's code paths. If a function jumps to code in another file, + and it's not a sibling call, objtool has no way to follow the jump + because it only analyzes a single file at a time. + +5. A callable function may not execute kernel entry/exit instructions. + The only code which needs such instructions is kernel entry code, + which shouldn't be be in callable functions anyway. + + This rule is just a sanity check to ensure that callable functions + return normally. + + +Errors in .S files +------------------ + +If you're getting an error in a compiled .S file which you don't +understand, first make sure that the affected code follows the above +rules. + +Here are some examples of common warnings reported by objtool, what +they mean, and suggestions for how to fix them. + + +1. asm_file.o: warning: objtool: func()+0x128: call without frame pointer save/setup + + The func() function made a function call without first saving and/or + updating the frame pointer. + + If func() is indeed a callable function, add proper frame pointer + logic using the FRAME_BEGIN and FRAME_END macros. Otherwise, remove + its ELF function annotation by changing ENDPROC to END. + + If you're getting this error in a .c file, see the "Errors in .c + files" section. + + +2. asm_file.o: warning: objtool: .text+0x53: return instruction outside of a callable function + + A return instruction was detected, but objtool couldn't find a way + for a callable function to reach the instruction. + + If the return instruction is inside (or reachable from) a callable + function, the function needs to be annotated with the ENTRY/ENDPROC + macros. + + If you _really_ need a return instruction outside of a function, and + are 100% sure that it won't affect stack traces, you can tell + objtool to ignore it. See the "Adding exceptions" section below. + + +3. asm_file.o: warning: objtool: func()+0x9: function has unreachable instruction + + The instruction lives inside of a callable function, but there's no + possible control flow path from the beginning of the function to the + instruction. + + If the instruction is actually needed, and it's actually in a + callable function, ensure that its function is properly annotated + with ENTRY/ENDPROC. + + If it's not actually in a callable function (e.g. kernel entry code), + change ENDPROC to END. + + +4. asm_file.o: warning: objtool: func(): can't find starting instruction + or + asm_file.o: warning: objtool: func()+0x11dd: can't decode instruction + + Did you put data in a text section? If so, that can confuse + objtool's instruction decoder. Move the data to a more appropriate + section like .data or .rodata. + + +5. asm_file.o: warning: objtool: func()+0x6: kernel entry/exit from callable instruction + + This is a kernel entry/exit instruction like sysenter or sysret. + Such instructions aren't allowed in a callable function, and are most + likely part of the kernel entry code. + + If the instruction isn't actually in a callable function, change + ENDPROC to END. + + +6. asm_file.o: warning: objtool: func()+0x26: sibling call from callable instruction with changed frame pointer + + This is a dynamic jump or a jump to an undefined symbol. Stacktool + assumed it's a sibling call and detected that the frame pointer + wasn't first restored to its original state. + + If it's not really a sibling call, you may need to move the + destination code to the local file. + + If the instruction is not actually in a callable function (e.g. + kernel entry code), change ENDPROC to END. + + +7. asm_file: warning: objtool: func()+0x5c: frame pointer state mismatch + + The instruction's frame pointer state is inconsistent, depending on + which execution path was taken to reach the instruction. + + Make sure the function pushes and sets up the frame pointer (for + x86_64, this means rbp) at the beginning of the function and pops it + at the end of the function. Also make sure that no other code in the + function touches the frame pointer. + + +Errors in .c files +------------------ + +If you're getting an objtool error in a compiled .c file, chances are +the file uses an asm() statement which has a "call" instruction. An +asm() statement with a call instruction must declare the use of the +stack pointer in its output operand. For example, on x86_64: + + register void *__sp asm("rsp"); + asm volatile("call func" : "+r" (__sp)); + +Otherwise the stack frame may not get created before the call. + +Another possible cause for errors in C code is if the Makefile removes +-fno-omit-frame-pointer or adds -fomit-frame-pointer to the gcc options. + +Also see the above section for .S file errors for more information what +the individual error messages mean. + +If the error doesn't seem to make sense, it could be a bug in objtool. +Feel free to ask the objtool maintainer for help. + + +Adding exceptions +----------------- + +If you _really_ need objtool to ignore something, and are 100% sure +that it won't affect kernel stack traces, you can tell objtool to +ignore it: + +- To skip validation of a function, use the STACK_FRAME_NON_STANDARD + macro. + +- To skip validation of a file, add + + OBJECT_FILES_NON_STANDARD_filename.o := n + + to the Makefile. + +- To skip validation of a directory, add + + OBJECT_FILES_NON_STANDARD := y + + to the Makefile. diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile new file mode 100644 index 000000000000..c4f0713a1eb7 --- /dev/null +++ b/tools/objtool/Makefile @@ -0,0 +1,60 @@ +include ../scripts/Makefile.include + +ifndef ($(ARCH)) +ARCH ?= $(shell uname -m) +ifeq ($(ARCH),x86_64) +ARCH := x86 +endif +endif + +ifeq ($(srctree),) +srctree := $(patsubst %/,%,$(dir $(shell pwd))) +srctree := $(patsubst %/,%,$(dir $(srctree))) +endif + +SUBCMD_SRCDIR = $(srctree)/tools/lib/subcmd/ +LIBSUBCMD = $(if $(OUTPUT),$(OUTPUT),$(SUBCMD_SRCDIR))libsubcmd.a + +OBJTOOL := $(OUTPUT)objtool +OBJTOOL_IN := $(OBJTOOL)-in.o + +all: $(OBJTOOL) + +INCLUDES := -I$(srctree)/tools/include +CFLAGS += -Wall -Werror $(EXTRA_WARNINGS) -fomit-frame-pointer -O2 $(INCLUDES) +LDFLAGS += -lelf $(LIBSUBCMD) + +AWK = awk +export srctree OUTPUT CFLAGS ARCH AWK +include $(srctree)/tools/build/Makefile.include + +$(OBJTOOL_IN): fixdep FORCE + @$(MAKE) $(build)=objtool + +$(OBJTOOL): $(LIBSUBCMD) $(OBJTOOL_IN) + @(test -d ../../kernel -a -d ../../tools -a -d ../objtool && (( \ + diff -I'^#include' arch/x86/insn/insn.c ../../arch/x86/lib/insn.c >/dev/null && \ + diff -I'^#include' arch/x86/insn/inat.c ../../arch/x86/lib/inat.c >/dev/null && \ + diff arch/x86/insn/x86-opcode-map.txt ../../arch/x86/lib/x86-opcode-map.txt >/dev/null && \ + diff arch/x86/insn/gen-insn-attr-x86.awk ../../arch/x86/tools/gen-insn-attr-x86.awk >/dev/null && \ + diff -I'^#include' arch/x86/insn/insn.h ../../arch/x86/include/asm/insn.h >/dev/null && \ + diff -I'^#include' arch/x86/insn/inat.h ../../arch/x86/include/asm/inat.h >/dev/null && \ + diff -I'^#include' arch/x86/insn/inat_types.h ../../arch/x86/include/asm/inat_types.h >/dev/null) \ + || echo "Warning: objtool: x86 instruction decoder differs from kernel" >&2 )) || true + $(QUIET_LINK)$(CC) $(OBJTOOL_IN) $(LDFLAGS) -o $@ + + +$(LIBSUBCMD): fixdep FORCE + $(Q)$(MAKE) -C $(SUBCMD_SRCDIR) + +$(LIBSUBCMD)-clean: + $(Q)$(MAKE) -C $(SUBCMD_SRCDIR) clean > /dev/null + +clean: $(LIBSUBCMD)-clean + $(call QUIET_CLEAN, objtool) $(RM) $(OBJTOOL) + $(Q)find $(OUTPUT) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete + $(Q)$(RM) $(OUTPUT)arch/x86/insn/inat-tables.c $(OUTPUT)fixdep + +FORCE: + +.PHONY: clean FORCE diff --git a/tools/objtool/arch.h b/tools/objtool/arch.h new file mode 100644 index 000000000000..f7350fcedc70 --- /dev/null +++ b/tools/objtool/arch.h @@ -0,0 +1,44 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#ifndef _ARCH_H +#define _ARCH_H + +#include +#include "elf.h" + +#define INSN_FP_SAVE 1 +#define INSN_FP_SETUP 2 +#define INSN_FP_RESTORE 3 +#define INSN_JUMP_CONDITIONAL 4 +#define INSN_JUMP_UNCONDITIONAL 5 +#define INSN_JUMP_DYNAMIC 6 +#define INSN_CALL 7 +#define INSN_CALL_DYNAMIC 8 +#define INSN_RETURN 9 +#define INSN_CONTEXT_SWITCH 10 +#define INSN_BUG 11 +#define INSN_NOP 12 +#define INSN_OTHER 13 +#define INSN_LAST INSN_OTHER + +int arch_decode_instruction(struct elf *elf, struct section *sec, + unsigned long offset, unsigned int maxlen, + unsigned int *len, unsigned char *type, + unsigned long *displacement); + +#endif /* _ARCH_H */ diff --git a/tools/objtool/arch/x86/Build b/tools/objtool/arch/x86/Build new file mode 100644 index 000000000000..debbdb0b5c43 --- /dev/null +++ b/tools/objtool/arch/x86/Build @@ -0,0 +1,12 @@ +objtool-y += decode.o + +inat_tables_script = arch/x86/insn/gen-insn-attr-x86.awk +inat_tables_maps = arch/x86/insn/x86-opcode-map.txt + +$(OUTPUT)arch/x86/insn/inat-tables.c: $(inat_tables_script) $(inat_tables_maps) + $(call rule_mkdir) + $(Q)$(call echo-cmd,gen)$(AWK) -f $(inat_tables_script) $(inat_tables_maps) > $@ + +$(OUTPUT)arch/x86/decode.o: $(OUTPUT)arch/x86/insn/inat-tables.c + +CFLAGS_decode.o += -I$(OUTPUT)arch/x86/insn diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c new file mode 100644 index 000000000000..c0c0b265e88e --- /dev/null +++ b/tools/objtool/arch/x86/decode.c @@ -0,0 +1,172 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#include +#include + +#define unlikely(cond) (cond) +#include "insn/insn.h" +#include "insn/inat.c" +#include "insn/insn.c" + +#include "../../elf.h" +#include "../../arch.h" +#include "../../warn.h" + +static int is_x86_64(struct elf *elf) +{ + switch (elf->ehdr.e_machine) { + case EM_X86_64: + return 1; + case EM_386: + return 0; + default: + WARN("unexpected ELF machine type %d", elf->ehdr.e_machine); + return -1; + } +} + +int arch_decode_instruction(struct elf *elf, struct section *sec, + unsigned long offset, unsigned int maxlen, + unsigned int *len, unsigned char *type, + unsigned long *immediate) +{ + struct insn insn; + int x86_64; + unsigned char op1, op2, ext; + + x86_64 = is_x86_64(elf); + if (x86_64 == -1) + return -1; + + insn_init(&insn, (void *)(sec->data + offset), maxlen, x86_64); + insn_get_length(&insn); + insn_get_opcode(&insn); + insn_get_modrm(&insn); + insn_get_immediate(&insn); + + if (!insn_complete(&insn)) { + WARN_FUNC("can't decode instruction", sec, offset); + return -1; + } + + *len = insn.length; + *type = INSN_OTHER; + + if (insn.vex_prefix.nbytes) + return 0; + + op1 = insn.opcode.bytes[0]; + op2 = insn.opcode.bytes[1]; + + switch (op1) { + case 0x55: + if (!insn.rex_prefix.nbytes) + /* push rbp */ + *type = INSN_FP_SAVE; + break; + + case 0x5d: + if (!insn.rex_prefix.nbytes) + /* pop rbp */ + *type = INSN_FP_RESTORE; + break; + + case 0x70 ... 0x7f: + *type = INSN_JUMP_CONDITIONAL; + break; + + case 0x89: + if (insn.rex_prefix.nbytes == 1 && + insn.rex_prefix.bytes[0] == 0x48 && + insn.modrm.nbytes && insn.modrm.bytes[0] == 0xe5) + /* mov rsp, rbp */ + *type = INSN_FP_SETUP; + break; + + case 0x90: + *type = INSN_NOP; + break; + + case 0x0f: + if (op2 >= 0x80 && op2 <= 0x8f) + *type = INSN_JUMP_CONDITIONAL; + else if (op2 == 0x05 || op2 == 0x07 || op2 == 0x34 || + op2 == 0x35) + /* sysenter, sysret */ + *type = INSN_CONTEXT_SWITCH; + else if (op2 == 0x0b || op2 == 0xb9) + /* ud2 */ + *type = INSN_BUG; + else if (op2 == 0x0d || op2 == 0x1f) + /* nopl/nopw */ + *type = INSN_NOP; + else if (op2 == 0x01 && insn.modrm.nbytes && + (insn.modrm.bytes[0] == 0xc2 || + insn.modrm.bytes[0] == 0xd8)) + /* vmlaunch, vmrun */ + *type = INSN_CONTEXT_SWITCH; + + break; + + case 0xc9: /* leave */ + *type = INSN_FP_RESTORE; + break; + + case 0xe3: /* jecxz/jrcxz */ + *type = INSN_JUMP_CONDITIONAL; + break; + + case 0xe9: + case 0xeb: + *type = INSN_JUMP_UNCONDITIONAL; + break; + + case 0xc2: + case 0xc3: + *type = INSN_RETURN; + break; + + case 0xc5: /* iret */ + case 0xca: /* retf */ + case 0xcb: /* retf */ + *type = INSN_CONTEXT_SWITCH; + break; + + case 0xe8: + *type = INSN_CALL; + break; + + case 0xff: + ext = X86_MODRM_REG(insn.modrm.bytes[0]); + if (ext == 2 || ext == 3) + *type = INSN_CALL_DYNAMIC; + else if (ext == 4) + *type = INSN_JUMP_DYNAMIC; + else if (ext == 5) /*jmpf */ + *type = INSN_CONTEXT_SWITCH; + + break; + + default: + break; + } + + *immediate = insn.immediate.nbytes ? insn.immediate.value : 0; + + return 0; +} diff --git a/tools/objtool/arch/x86/insn/gen-insn-attr-x86.awk b/tools/objtool/arch/x86/insn/gen-insn-attr-x86.awk new file mode 100644 index 000000000000..093a892026f9 --- /dev/null +++ b/tools/objtool/arch/x86/insn/gen-insn-attr-x86.awk @@ -0,0 +1,387 @@ +#!/bin/awk -f +# gen-insn-attr-x86.awk: Instruction attribute table generator +# Written by Masami Hiramatsu +# +# Usage: awk -f gen-insn-attr-x86.awk x86-opcode-map.txt > inat-tables.c + +# Awk implementation sanity check +function check_awk_implement() { + if (sprintf("%x", 0) != "0") + return "Your awk has a printf-format problem." + return "" +} + +# Clear working vars +function clear_vars() { + delete table + delete lptable2 + delete lptable1 + delete lptable3 + eid = -1 # escape id + gid = -1 # group id + aid = -1 # AVX id + tname = "" +} + +BEGIN { + # Implementation error checking + awkchecked = check_awk_implement() + if (awkchecked != "") { + print "Error: " awkchecked > "/dev/stderr" + print "Please try to use gawk." > "/dev/stderr" + exit 1 + } + + # Setup generating tables + print "/* x86 opcode map generated from x86-opcode-map.txt */" + print "/* Do not change this code. */\n" + ggid = 1 + geid = 1 + gaid = 0 + delete etable + delete gtable + delete atable + + opnd_expr = "^[A-Za-z/]" + ext_expr = "^\\(" + sep_expr = "^\\|$" + group_expr = "^Grp[0-9A-Za-z]+" + + imm_expr = "^[IJAOL][a-z]" + imm_flag["Ib"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)" + imm_flag["Jb"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)" + imm_flag["Iw"] = "INAT_MAKE_IMM(INAT_IMM_WORD)" + imm_flag["Id"] = "INAT_MAKE_IMM(INAT_IMM_DWORD)" + imm_flag["Iq"] = "INAT_MAKE_IMM(INAT_IMM_QWORD)" + imm_flag["Ap"] = "INAT_MAKE_IMM(INAT_IMM_PTR)" + imm_flag["Iz"] = "INAT_MAKE_IMM(INAT_IMM_VWORD32)" + imm_flag["Jz"] = "INAT_MAKE_IMM(INAT_IMM_VWORD32)" + imm_flag["Iv"] = "INAT_MAKE_IMM(INAT_IMM_VWORD)" + imm_flag["Ob"] = "INAT_MOFFSET" + imm_flag["Ov"] = "INAT_MOFFSET" + imm_flag["Lx"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)" + + modrm_expr = "^([CDEGMNPQRSUVW/][a-z]+|NTA|T[012])" + force64_expr = "\\([df]64\\)" + rex_expr = "^REX(\\.[XRWB]+)*" + fpu_expr = "^ESC" # TODO + + lprefix1_expr = "\\((66|!F3)\\)" + lprefix2_expr = "\\(F3\\)" + lprefix3_expr = "\\((F2|!F3|66\\&F2)\\)" + lprefix_expr = "\\((66|F2|F3)\\)" + max_lprefix = 4 + + # All opcodes starting with lower-case 'v' or with (v1) superscript + # accepts VEX prefix + vexok_opcode_expr = "^v.*" + vexok_expr = "\\(v1\\)" + # All opcodes with (v) superscript supports *only* VEX prefix + vexonly_expr = "\\(v\\)" + + prefix_expr = "\\(Prefix\\)" + prefix_num["Operand-Size"] = "INAT_PFX_OPNDSZ" + prefix_num["REPNE"] = "INAT_PFX_REPNE" + prefix_num["REP/REPE"] = "INAT_PFX_REPE" + prefix_num["XACQUIRE"] = "INAT_PFX_REPNE" + prefix_num["XRELEASE"] = "INAT_PFX_REPE" + prefix_num["LOCK"] = "INAT_PFX_LOCK" + prefix_num["SEG=CS"] = "INAT_PFX_CS" + prefix_num["SEG=DS"] = "INAT_PFX_DS" + prefix_num["SEG=ES"] = "INAT_PFX_ES" + prefix_num["SEG=FS"] = "INAT_PFX_FS" + prefix_num["SEG=GS"] = "INAT_PFX_GS" + prefix_num["SEG=SS"] = "INAT_PFX_SS" + prefix_num["Address-Size"] = "INAT_PFX_ADDRSZ" + prefix_num["VEX+1byte"] = "INAT_PFX_VEX2" + prefix_num["VEX+2byte"] = "INAT_PFX_VEX3" + + clear_vars() +} + +function semantic_error(msg) { + print "Semantic error at " NR ": " msg > "/dev/stderr" + exit 1 +} + +function debug(msg) { + print "DEBUG: " msg +} + +function array_size(arr, i,c) { + c = 0 + for (i in arr) + c++ + return c +} + +/^Table:/ { + print "/* " $0 " */" + if (tname != "") + semantic_error("Hit Table: before EndTable:."); +} + +/^Referrer:/ { + if (NF != 1) { + # escape opcode table + ref = "" + for (i = 2; i <= NF; i++) + ref = ref $i + eid = escape[ref] + tname = sprintf("inat_escape_table_%d", eid) + } +} + +/^AVXcode:/ { + if (NF != 1) { + # AVX/escape opcode table + aid = $2 + if (gaid <= aid) + gaid = aid + 1 + if (tname == "") # AVX only opcode table + tname = sprintf("inat_avx_table_%d", $2) + } + if (aid == -1 && eid == -1) # primary opcode table + tname = "inat_primary_table" +} + +/^GrpTable:/ { + print "/* " $0 " */" + if (!($2 in group)) + semantic_error("No group: " $2 ) + gid = group[$2] + tname = "inat_group_table_" gid +} + +function print_table(tbl,name,fmt,n) +{ + print "const insn_attr_t " name " = {" + for (i = 0; i < n; i++) { + id = sprintf(fmt, i) + if (tbl[id]) + print " [" id "] = " tbl[id] "," + } + print "};" +} + +/^EndTable/ { + if (gid != -1) { + # print group tables + if (array_size(table) != 0) { + print_table(table, tname "[INAT_GROUP_TABLE_SIZE]", + "0x%x", 8) + gtable[gid,0] = tname + } + if (array_size(lptable1) != 0) { + print_table(lptable1, tname "_1[INAT_GROUP_TABLE_SIZE]", + "0x%x", 8) + gtable[gid,1] = tname "_1" + } + if (array_size(lptable2) != 0) { + print_table(lptable2, tname "_2[INAT_GROUP_TABLE_SIZE]", + "0x%x", 8) + gtable[gid,2] = tname "_2" + } + if (array_size(lptable3) != 0) { + print_table(lptable3, tname "_3[INAT_GROUP_TABLE_SIZE]", + "0x%x", 8) + gtable[gid,3] = tname "_3" + } + } else { + # print primary/escaped tables + if (array_size(table) != 0) { + print_table(table, tname "[INAT_OPCODE_TABLE_SIZE]", + "0x%02x", 256) + etable[eid,0] = tname + if (aid >= 0) + atable[aid,0] = tname + } + if (array_size(lptable1) != 0) { + print_table(lptable1,tname "_1[INAT_OPCODE_TABLE_SIZE]", + "0x%02x", 256) + etable[eid,1] = tname "_1" + if (aid >= 0) + atable[aid,1] = tname "_1" + } + if (array_size(lptable2) != 0) { + print_table(lptable2,tname "_2[INAT_OPCODE_TABLE_SIZE]", + "0x%02x", 256) + etable[eid,2] = tname "_2" + if (aid >= 0) + atable[aid,2] = tname "_2" + } + if (array_size(lptable3) != 0) { + print_table(lptable3,tname "_3[INAT_OPCODE_TABLE_SIZE]", + "0x%02x", 256) + etable[eid,3] = tname "_3" + if (aid >= 0) + atable[aid,3] = tname "_3" + } + } + print "" + clear_vars() +} + +function add_flags(old,new) { + if (old && new) + return old " | " new + else if (old) + return old + else + return new +} + +# convert operands to flags. +function convert_operands(count,opnd, i,j,imm,mod) +{ + imm = null + mod = null + for (j = 1; j <= count; j++) { + i = opnd[j] + if (match(i, imm_expr) == 1) { + if (!imm_flag[i]) + semantic_error("Unknown imm opnd: " i) + if (imm) { + if (i != "Ib") + semantic_error("Second IMM error") + imm = add_flags(imm, "INAT_SCNDIMM") + } else + imm = imm_flag[i] + } else if (match(i, modrm_expr)) + mod = "INAT_MODRM" + } + return add_flags(imm, mod) +} + +/^[0-9a-f]+\:/ { + if (NR == 1) + next + # get index + idx = "0x" substr($1, 1, index($1,":") - 1) + if (idx in table) + semantic_error("Redefine " idx " in " tname) + + # check if escaped opcode + if ("escape" == $2) { + if ($3 != "#") + semantic_error("No escaped name") + ref = "" + for (i = 4; i <= NF; i++) + ref = ref $i + if (ref in escape) + semantic_error("Redefine escape (" ref ")") + escape[ref] = geid + geid++ + table[idx] = "INAT_MAKE_ESCAPE(" escape[ref] ")" + next + } + + variant = null + # converts + i = 2 + while (i <= NF) { + opcode = $(i++) + delete opnds + ext = null + flags = null + opnd = null + # parse one opcode + if (match($i, opnd_expr)) { + opnd = $i + count = split($(i++), opnds, ",") + flags = convert_operands(count, opnds) + } + if (match($i, ext_expr)) + ext = $(i++) + if (match($i, sep_expr)) + i++ + else if (i < NF) + semantic_error($i " is not a separator") + + # check if group opcode + if (match(opcode, group_expr)) { + if (!(opcode in group)) { + group[opcode] = ggid + ggid++ + } + flags = add_flags(flags, "INAT_MAKE_GROUP(" group[opcode] ")") + } + # check force(or default) 64bit + if (match(ext, force64_expr)) + flags = add_flags(flags, "INAT_FORCE64") + + # check REX prefix + if (match(opcode, rex_expr)) + flags = add_flags(flags, "INAT_MAKE_PREFIX(INAT_PFX_REX)") + + # check coprocessor escape : TODO + if (match(opcode, fpu_expr)) + flags = add_flags(flags, "INAT_MODRM") + + # check VEX codes + if (match(ext, vexonly_expr)) + flags = add_flags(flags, "INAT_VEXOK | INAT_VEXONLY") + else if (match(ext, vexok_expr) || match(opcode, vexok_opcode_expr)) + flags = add_flags(flags, "INAT_VEXOK") + + # check prefixes + if (match(ext, prefix_expr)) { + if (!prefix_num[opcode]) + semantic_error("Unknown prefix: " opcode) + flags = add_flags(flags, "INAT_MAKE_PREFIX(" prefix_num[opcode] ")") + } + if (length(flags) == 0) + continue + # check if last prefix + if (match(ext, lprefix1_expr)) { + lptable1[idx] = add_flags(lptable1[idx],flags) + variant = "INAT_VARIANT" + } + if (match(ext, lprefix2_expr)) { + lptable2[idx] = add_flags(lptable2[idx],flags) + variant = "INAT_VARIANT" + } + if (match(ext, lprefix3_expr)) { + lptable3[idx] = add_flags(lptable3[idx],flags) + variant = "INAT_VARIANT" + } + if (!match(ext, lprefix_expr)){ + table[idx] = add_flags(table[idx],flags) + } + } + if (variant) + table[idx] = add_flags(table[idx],variant) +} + +END { + if (awkchecked != "") + exit 1 + # print escape opcode map's array + print "/* Escape opcode map array */" + print "const insn_attr_t * const inat_escape_tables[INAT_ESC_MAX + 1]" \ + "[INAT_LSTPFX_MAX + 1] = {" + for (i = 0; i < geid; i++) + for (j = 0; j < max_lprefix; j++) + if (etable[i,j]) + print " ["i"]["j"] = "etable[i,j]"," + print "};\n" + # print group opcode map's array + print "/* Group opcode map array */" + print "const insn_attr_t * const inat_group_tables[INAT_GRP_MAX + 1]"\ + "[INAT_LSTPFX_MAX + 1] = {" + for (i = 0; i < ggid; i++) + for (j = 0; j < max_lprefix; j++) + if (gtable[i,j]) + print " ["i"]["j"] = "gtable[i,j]"," + print "};\n" + # print AVX opcode map's array + print "/* AVX opcode map array */" + print "const insn_attr_t * const inat_avx_tables[X86_VEX_M_MAX + 1]"\ + "[INAT_LSTPFX_MAX + 1] = {" + for (i = 0; i < gaid; i++) + for (j = 0; j < max_lprefix; j++) + if (atable[i,j]) + print " ["i"]["j"] = "atable[i,j]"," + print "};" +} + diff --git a/tools/objtool/arch/x86/insn/inat.c b/tools/objtool/arch/x86/insn/inat.c new file mode 100644 index 000000000000..e4bf28e6f4c7 --- /dev/null +++ b/tools/objtool/arch/x86/insn/inat.c @@ -0,0 +1,97 @@ +/* + * x86 instruction attribute tables + * + * Written by Masami Hiramatsu + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + */ +#include "insn.h" + +/* Attribute tables are generated from opcode map */ +#include "inat-tables.c" + +/* Attribute search APIs */ +insn_attr_t inat_get_opcode_attribute(insn_byte_t opcode) +{ + return inat_primary_table[opcode]; +} + +int inat_get_last_prefix_id(insn_byte_t last_pfx) +{ + insn_attr_t lpfx_attr; + + lpfx_attr = inat_get_opcode_attribute(last_pfx); + return inat_last_prefix_id(lpfx_attr); +} + +insn_attr_t inat_get_escape_attribute(insn_byte_t opcode, int lpfx_id, + insn_attr_t esc_attr) +{ + const insn_attr_t *table; + int n; + + n = inat_escape_id(esc_attr); + + table = inat_escape_tables[n][0]; + if (!table) + return 0; + if (inat_has_variant(table[opcode]) && lpfx_id) { + table = inat_escape_tables[n][lpfx_id]; + if (!table) + return 0; + } + return table[opcode]; +} + +insn_attr_t inat_get_group_attribute(insn_byte_t modrm, int lpfx_id, + insn_attr_t grp_attr) +{ + const insn_attr_t *table; + int n; + + n = inat_group_id(grp_attr); + + table = inat_group_tables[n][0]; + if (!table) + return inat_group_common_attribute(grp_attr); + if (inat_has_variant(table[X86_MODRM_REG(modrm)]) && lpfx_id) { + table = inat_group_tables[n][lpfx_id]; + if (!table) + return inat_group_common_attribute(grp_attr); + } + return table[X86_MODRM_REG(modrm)] | + inat_group_common_attribute(grp_attr); +} + +insn_attr_t inat_get_avx_attribute(insn_byte_t opcode, insn_byte_t vex_m, + insn_byte_t vex_p) +{ + const insn_attr_t *table; + if (vex_m > X86_VEX_M_MAX || vex_p > INAT_LSTPFX_MAX) + return 0; + /* At first, this checks the master table */ + table = inat_avx_tables[vex_m][0]; + if (!table) + return 0; + if (!inat_is_group(table[opcode]) && vex_p) { + /* If this is not a group, get attribute directly */ + table = inat_avx_tables[vex_m][vex_p]; + if (!table) + return 0; + } + return table[opcode]; +} + diff --git a/tools/objtool/arch/x86/insn/inat.h b/tools/objtool/arch/x86/insn/inat.h new file mode 100644 index 000000000000..611645e903a8 --- /dev/null +++ b/tools/objtool/arch/x86/insn/inat.h @@ -0,0 +1,221 @@ +#ifndef _ASM_X86_INAT_H +#define _ASM_X86_INAT_H +/* + * x86 instruction attributes + * + * Written by Masami Hiramatsu + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + */ +#include "inat_types.h" + +/* + * Internal bits. Don't use bitmasks directly, because these bits are + * unstable. You should use checking functions. + */ + +#define INAT_OPCODE_TABLE_SIZE 256 +#define INAT_GROUP_TABLE_SIZE 8 + +/* Legacy last prefixes */ +#define INAT_PFX_OPNDSZ 1 /* 0x66 */ /* LPFX1 */ +#define INAT_PFX_REPE 2 /* 0xF3 */ /* LPFX2 */ +#define INAT_PFX_REPNE 3 /* 0xF2 */ /* LPFX3 */ +/* Other Legacy prefixes */ +#define INAT_PFX_LOCK 4 /* 0xF0 */ +#define INAT_PFX_CS 5 /* 0x2E */ +#define INAT_PFX_DS 6 /* 0x3E */ +#define INAT_PFX_ES 7 /* 0x26 */ +#define INAT_PFX_FS 8 /* 0x64 */ +#define INAT_PFX_GS 9 /* 0x65 */ +#define INAT_PFX_SS 10 /* 0x36 */ +#define INAT_PFX_ADDRSZ 11 /* 0x67 */ +/* x86-64 REX prefix */ +#define INAT_PFX_REX 12 /* 0x4X */ +/* AVX VEX prefixes */ +#define INAT_PFX_VEX2 13 /* 2-bytes VEX prefix */ +#define INAT_PFX_VEX3 14 /* 3-bytes VEX prefix */ + +#define INAT_LSTPFX_MAX 3 +#define INAT_LGCPFX_MAX 11 + +/* Immediate size */ +#define INAT_IMM_BYTE 1 +#define INAT_IMM_WORD 2 +#define INAT_IMM_DWORD 3 +#define INAT_IMM_QWORD 4 +#define INAT_IMM_PTR 5 +#define INAT_IMM_VWORD32 6 +#define INAT_IMM_VWORD 7 + +/* Legacy prefix */ +#define INAT_PFX_OFFS 0 +#define INAT_PFX_BITS 4 +#define INAT_PFX_MAX ((1 << INAT_PFX_BITS) - 1) +#define INAT_PFX_MASK (INAT_PFX_MAX << INAT_PFX_OFFS) +/* Escape opcodes */ +#define INAT_ESC_OFFS (INAT_PFX_OFFS + INAT_PFX_BITS) +#define INAT_ESC_BITS 2 +#define INAT_ESC_MAX ((1 << INAT_ESC_BITS) - 1) +#define INAT_ESC_MASK (INAT_ESC_MAX << INAT_ESC_OFFS) +/* Group opcodes (1-16) */ +#define INAT_GRP_OFFS (INAT_ESC_OFFS + INAT_ESC_BITS) +#define INAT_GRP_BITS 5 +#define INAT_GRP_MAX ((1 << INAT_GRP_BITS) - 1) +#define INAT_GRP_MASK (INAT_GRP_MAX << INAT_GRP_OFFS) +/* Immediates */ +#define INAT_IMM_OFFS (INAT_GRP_OFFS + INAT_GRP_BITS) +#define INAT_IMM_BITS 3 +#define INAT_IMM_MASK (((1 << INAT_IMM_BITS) - 1) << INAT_IMM_OFFS) +/* Flags */ +#define INAT_FLAG_OFFS (INAT_IMM_OFFS + INAT_IMM_BITS) +#define INAT_MODRM (1 << (INAT_FLAG_OFFS)) +#define INAT_FORCE64 (1 << (INAT_FLAG_OFFS + 1)) +#define INAT_SCNDIMM (1 << (INAT_FLAG_OFFS + 2)) +#define INAT_MOFFSET (1 << (INAT_FLAG_OFFS + 3)) +#define INAT_VARIANT (1 << (INAT_FLAG_OFFS + 4)) +#define INAT_VEXOK (1 << (INAT_FLAG_OFFS + 5)) +#define INAT_VEXONLY (1 << (INAT_FLAG_OFFS + 6)) +/* Attribute making macros for attribute tables */ +#define INAT_MAKE_PREFIX(pfx) (pfx << INAT_PFX_OFFS) +#define INAT_MAKE_ESCAPE(esc) (esc << INAT_ESC_OFFS) +#define INAT_MAKE_GROUP(grp) ((grp << INAT_GRP_OFFS) | INAT_MODRM) +#define INAT_MAKE_IMM(imm) (imm << INAT_IMM_OFFS) + +/* Attribute search APIs */ +extern insn_attr_t inat_get_opcode_attribute(insn_byte_t opcode); +extern int inat_get_last_prefix_id(insn_byte_t last_pfx); +extern insn_attr_t inat_get_escape_attribute(insn_byte_t opcode, + int lpfx_id, + insn_attr_t esc_attr); +extern insn_attr_t inat_get_group_attribute(insn_byte_t modrm, + int lpfx_id, + insn_attr_t esc_attr); +extern insn_attr_t inat_get_avx_attribute(insn_byte_t opcode, + insn_byte_t vex_m, + insn_byte_t vex_pp); + +/* Attribute checking functions */ +static inline int inat_is_legacy_prefix(insn_attr_t attr) +{ + attr &= INAT_PFX_MASK; + return attr && attr <= INAT_LGCPFX_MAX; +} + +static inline int inat_is_address_size_prefix(insn_attr_t attr) +{ + return (attr & INAT_PFX_MASK) == INAT_PFX_ADDRSZ; +} + +static inline int inat_is_operand_size_prefix(insn_attr_t attr) +{ + return (attr & INAT_PFX_MASK) == INAT_PFX_OPNDSZ; +} + +static inline int inat_is_rex_prefix(insn_attr_t attr) +{ + return (attr & INAT_PFX_MASK) == INAT_PFX_REX; +} + +static inline int inat_last_prefix_id(insn_attr_t attr) +{ + if ((attr & INAT_PFX_MASK) > INAT_LSTPFX_MAX) + return 0; + else + return attr & INAT_PFX_MASK; +} + +static inline int inat_is_vex_prefix(insn_attr_t attr) +{ + attr &= INAT_PFX_MASK; + return attr == INAT_PFX_VEX2 || attr == INAT_PFX_VEX3; +} + +static inline int inat_is_vex3_prefix(insn_attr_t attr) +{ + return (attr & INAT_PFX_MASK) == INAT_PFX_VEX3; +} + +static inline int inat_is_escape(insn_attr_t attr) +{ + return attr & INAT_ESC_MASK; +} + +static inline int inat_escape_id(insn_attr_t attr) +{ + return (attr & INAT_ESC_MASK) >> INAT_ESC_OFFS; +} + +static inline int inat_is_group(insn_attr_t attr) +{ + return attr & INAT_GRP_MASK; +} + +static inline int inat_group_id(insn_attr_t attr) +{ + return (attr & INAT_GRP_MASK) >> INAT_GRP_OFFS; +} + +static inline int inat_group_common_attribute(insn_attr_t attr) +{ + return attr & ~INAT_GRP_MASK; +} + +static inline int inat_has_immediate(insn_attr_t attr) +{ + return attr & INAT_IMM_MASK; +} + +static inline int inat_immediate_size(insn_attr_t attr) +{ + return (attr & INAT_IMM_MASK) >> INAT_IMM_OFFS; +} + +static inline int inat_has_modrm(insn_attr_t attr) +{ + return attr & INAT_MODRM; +} + +static inline int inat_is_force64(insn_attr_t attr) +{ + return attr & INAT_FORCE64; +} + +static inline int inat_has_second_immediate(insn_attr_t attr) +{ + return attr & INAT_SCNDIMM; +} + +static inline int inat_has_moffset(insn_attr_t attr) +{ + return attr & INAT_MOFFSET; +} + +static inline int inat_has_variant(insn_attr_t attr) +{ + return attr & INAT_VARIANT; +} + +static inline int inat_accept_vex(insn_attr_t attr) +{ + return attr & INAT_VEXOK; +} + +static inline int inat_must_vex(insn_attr_t attr) +{ + return attr & INAT_VEXONLY; +} +#endif diff --git a/tools/objtool/arch/x86/insn/inat_types.h b/tools/objtool/arch/x86/insn/inat_types.h new file mode 100644 index 000000000000..cb3c20ce39cf --- /dev/null +++ b/tools/objtool/arch/x86/insn/inat_types.h @@ -0,0 +1,29 @@ +#ifndef _ASM_X86_INAT_TYPES_H +#define _ASM_X86_INAT_TYPES_H +/* + * x86 instruction attributes + * + * Written by Masami Hiramatsu + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + */ + +/* Instruction attributes */ +typedef unsigned int insn_attr_t; +typedef unsigned char insn_byte_t; +typedef signed int insn_value_t; + +#endif diff --git a/tools/objtool/arch/x86/insn/insn.c b/tools/objtool/arch/x86/insn/insn.c new file mode 100644 index 000000000000..47314a64399c --- /dev/null +++ b/tools/objtool/arch/x86/insn/insn.c @@ -0,0 +1,594 @@ +/* + * x86 instruction analysis + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2002, 2004, 2009 + */ + +#ifdef __KERNEL__ +#include +#else +#include +#endif +#include "inat.h" +#include "insn.h" + +/* Verify next sizeof(t) bytes can be on the same instruction */ +#define validate_next(t, insn, n) \ + ((insn)->next_byte + sizeof(t) + n <= (insn)->end_kaddr) + +#define __get_next(t, insn) \ + ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); r; }) + +#define __peek_nbyte_next(t, insn, n) \ + ({ t r = *(t*)((insn)->next_byte + n); r; }) + +#define get_next(t, insn) \ + ({ if (unlikely(!validate_next(t, insn, 0))) goto err_out; __get_next(t, insn); }) + +#define peek_nbyte_next(t, insn, n) \ + ({ if (unlikely(!validate_next(t, insn, n))) goto err_out; __peek_nbyte_next(t, insn, n); }) + +#define peek_next(t, insn) peek_nbyte_next(t, insn, 0) + +/** + * insn_init() - initialize struct insn + * @insn: &struct insn to be initialized + * @kaddr: address (in kernel memory) of instruction (or copy thereof) + * @x86_64: !0 for 64-bit kernel or 64-bit app + */ +void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64) +{ + /* + * Instructions longer than MAX_INSN_SIZE (15 bytes) are invalid + * even if the input buffer is long enough to hold them. + */ + if (buf_len > MAX_INSN_SIZE) + buf_len = MAX_INSN_SIZE; + + memset(insn, 0, sizeof(*insn)); + insn->kaddr = kaddr; + insn->end_kaddr = kaddr + buf_len; + insn->next_byte = kaddr; + insn->x86_64 = x86_64 ? 1 : 0; + insn->opnd_bytes = 4; + if (x86_64) + insn->addr_bytes = 8; + else + insn->addr_bytes = 4; +} + +/** + * insn_get_prefixes - scan x86 instruction prefix bytes + * @insn: &struct insn containing instruction + * + * Populates the @insn->prefixes bitmap, and updates @insn->next_byte + * to point to the (first) opcode. No effect if @insn->prefixes.got + * is already set. + */ +void insn_get_prefixes(struct insn *insn) +{ + struct insn_field *prefixes = &insn->prefixes; + insn_attr_t attr; + insn_byte_t b, lb; + int i, nb; + + if (prefixes->got) + return; + + nb = 0; + lb = 0; + b = peek_next(insn_byte_t, insn); + attr = inat_get_opcode_attribute(b); + while (inat_is_legacy_prefix(attr)) { + /* Skip if same prefix */ + for (i = 0; i < nb; i++) + if (prefixes->bytes[i] == b) + goto found; + if (nb == 4) + /* Invalid instruction */ + break; + prefixes->bytes[nb++] = b; + if (inat_is_address_size_prefix(attr)) { + /* address size switches 2/4 or 4/8 */ + if (insn->x86_64) + insn->addr_bytes ^= 12; + else + insn->addr_bytes ^= 6; + } else if (inat_is_operand_size_prefix(attr)) { + /* oprand size switches 2/4 */ + insn->opnd_bytes ^= 6; + } +found: + prefixes->nbytes++; + insn->next_byte++; + lb = b; + b = peek_next(insn_byte_t, insn); + attr = inat_get_opcode_attribute(b); + } + /* Set the last prefix */ + if (lb && lb != insn->prefixes.bytes[3]) { + if (unlikely(insn->prefixes.bytes[3])) { + /* Swap the last prefix */ + b = insn->prefixes.bytes[3]; + for (i = 0; i < nb; i++) + if (prefixes->bytes[i] == lb) + prefixes->bytes[i] = b; + } + insn->prefixes.bytes[3] = lb; + } + + /* Decode REX prefix */ + if (insn->x86_64) { + b = peek_next(insn_byte_t, insn); + attr = inat_get_opcode_attribute(b); + if (inat_is_rex_prefix(attr)) { + insn->rex_prefix.value = b; + insn->rex_prefix.nbytes = 1; + insn->next_byte++; + if (X86_REX_W(b)) + /* REX.W overrides opnd_size */ + insn->opnd_bytes = 8; + } + } + insn->rex_prefix.got = 1; + + /* Decode VEX prefix */ + b = peek_next(insn_byte_t, insn); + attr = inat_get_opcode_attribute(b); + if (inat_is_vex_prefix(attr)) { + insn_byte_t b2 = peek_nbyte_next(insn_byte_t, insn, 1); + if (!insn->x86_64) { + /* + * In 32-bits mode, if the [7:6] bits (mod bits of + * ModRM) on the second byte are not 11b, it is + * LDS or LES. + */ + if (X86_MODRM_MOD(b2) != 3) + goto vex_end; + } + insn->vex_prefix.bytes[0] = b; + insn->vex_prefix.bytes[1] = b2; + if (inat_is_vex3_prefix(attr)) { + b2 = peek_nbyte_next(insn_byte_t, insn, 2); + insn->vex_prefix.bytes[2] = b2; + insn->vex_prefix.nbytes = 3; + insn->next_byte += 3; + if (insn->x86_64 && X86_VEX_W(b2)) + /* VEX.W overrides opnd_size */ + insn->opnd_bytes = 8; + } else { + /* + * For VEX2, fake VEX3-like byte#2. + * Makes it easier to decode vex.W, vex.vvvv, + * vex.L and vex.pp. Masking with 0x7f sets vex.W == 0. + */ + insn->vex_prefix.bytes[2] = b2 & 0x7f; + insn->vex_prefix.nbytes = 2; + insn->next_byte += 2; + } + } +vex_end: + insn->vex_prefix.got = 1; + + prefixes->got = 1; + +err_out: + return; +} + +/** + * insn_get_opcode - collect opcode(s) + * @insn: &struct insn containing instruction + * + * Populates @insn->opcode, updates @insn->next_byte to point past the + * opcode byte(s), and set @insn->attr (except for groups). + * If necessary, first collects any preceding (prefix) bytes. + * Sets @insn->opcode.value = opcode1. No effect if @insn->opcode.got + * is already 1. + */ +void insn_get_opcode(struct insn *insn) +{ + struct insn_field *opcode = &insn->opcode; + insn_byte_t op; + int pfx_id; + if (opcode->got) + return; + if (!insn->prefixes.got) + insn_get_prefixes(insn); + + /* Get first opcode */ + op = get_next(insn_byte_t, insn); + opcode->bytes[0] = op; + opcode->nbytes = 1; + + /* Check if there is VEX prefix or not */ + if (insn_is_avx(insn)) { + insn_byte_t m, p; + m = insn_vex_m_bits(insn); + p = insn_vex_p_bits(insn); + insn->attr = inat_get_avx_attribute(op, m, p); + if (!inat_accept_vex(insn->attr) && !inat_is_group(insn->attr)) + insn->attr = 0; /* This instruction is bad */ + goto end; /* VEX has only 1 byte for opcode */ + } + + insn->attr = inat_get_opcode_attribute(op); + while (inat_is_escape(insn->attr)) { + /* Get escaped opcode */ + op = get_next(insn_byte_t, insn); + opcode->bytes[opcode->nbytes++] = op; + pfx_id = insn_last_prefix_id(insn); + insn->attr = inat_get_escape_attribute(op, pfx_id, insn->attr); + } + if (inat_must_vex(insn->attr)) + insn->attr = 0; /* This instruction is bad */ +end: + opcode->got = 1; + +err_out: + return; +} + +/** + * insn_get_modrm - collect ModRM byte, if any + * @insn: &struct insn containing instruction + * + * Populates @insn->modrm and updates @insn->next_byte to point past the + * ModRM byte, if any. If necessary, first collects the preceding bytes + * (prefixes and opcode(s)). No effect if @insn->modrm.got is already 1. + */ +void insn_get_modrm(struct insn *insn) +{ + struct insn_field *modrm = &insn->modrm; + insn_byte_t pfx_id, mod; + if (modrm->got) + return; + if (!insn->opcode.got) + insn_get_opcode(insn); + + if (inat_has_modrm(insn->attr)) { + mod = get_next(insn_byte_t, insn); + modrm->value = mod; + modrm->nbytes = 1; + if (inat_is_group(insn->attr)) { + pfx_id = insn_last_prefix_id(insn); + insn->attr = inat_get_group_attribute(mod, pfx_id, + insn->attr); + if (insn_is_avx(insn) && !inat_accept_vex(insn->attr)) + insn->attr = 0; /* This is bad */ + } + } + + if (insn->x86_64 && inat_is_force64(insn->attr)) + insn->opnd_bytes = 8; + modrm->got = 1; + +err_out: + return; +} + + +/** + * insn_rip_relative() - Does instruction use RIP-relative addressing mode? + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * ModRM byte. No effect if @insn->x86_64 is 0. + */ +int insn_rip_relative(struct insn *insn) +{ + struct insn_field *modrm = &insn->modrm; + + if (!insn->x86_64) + return 0; + if (!modrm->got) + insn_get_modrm(insn); + /* + * For rip-relative instructions, the mod field (top 2 bits) + * is zero and the r/m field (bottom 3 bits) is 0x5. + */ + return (modrm->nbytes && (modrm->value & 0xc7) == 0x5); +} + +/** + * insn_get_sib() - Get the SIB byte of instruction + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * ModRM byte. + */ +void insn_get_sib(struct insn *insn) +{ + insn_byte_t modrm; + + if (insn->sib.got) + return; + if (!insn->modrm.got) + insn_get_modrm(insn); + if (insn->modrm.nbytes) { + modrm = (insn_byte_t)insn->modrm.value; + if (insn->addr_bytes != 2 && + X86_MODRM_MOD(modrm) != 3 && X86_MODRM_RM(modrm) == 4) { + insn->sib.value = get_next(insn_byte_t, insn); + insn->sib.nbytes = 1; + } + } + insn->sib.got = 1; + +err_out: + return; +} + + +/** + * insn_get_displacement() - Get the displacement of instruction + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * SIB byte. + * Displacement value is sign-expanded. + */ +void insn_get_displacement(struct insn *insn) +{ + insn_byte_t mod, rm, base; + + if (insn->displacement.got) + return; + if (!insn->sib.got) + insn_get_sib(insn); + if (insn->modrm.nbytes) { + /* + * Interpreting the modrm byte: + * mod = 00 - no displacement fields (exceptions below) + * mod = 01 - 1-byte displacement field + * mod = 10 - displacement field is 4 bytes, or 2 bytes if + * address size = 2 (0x67 prefix in 32-bit mode) + * mod = 11 - no memory operand + * + * If address size = 2... + * mod = 00, r/m = 110 - displacement field is 2 bytes + * + * If address size != 2... + * mod != 11, r/m = 100 - SIB byte exists + * mod = 00, SIB base = 101 - displacement field is 4 bytes + * mod = 00, r/m = 101 - rip-relative addressing, displacement + * field is 4 bytes + */ + mod = X86_MODRM_MOD(insn->modrm.value); + rm = X86_MODRM_RM(insn->modrm.value); + base = X86_SIB_BASE(insn->sib.value); + if (mod == 3) + goto out; + if (mod == 1) { + insn->displacement.value = get_next(char, insn); + insn->displacement.nbytes = 1; + } else if (insn->addr_bytes == 2) { + if ((mod == 0 && rm == 6) || mod == 2) { + insn->displacement.value = + get_next(short, insn); + insn->displacement.nbytes = 2; + } + } else { + if ((mod == 0 && rm == 5) || mod == 2 || + (mod == 0 && base == 5)) { + insn->displacement.value = get_next(int, insn); + insn->displacement.nbytes = 4; + } + } + } +out: + insn->displacement.got = 1; + +err_out: + return; +} + +/* Decode moffset16/32/64. Return 0 if failed */ +static int __get_moffset(struct insn *insn) +{ + switch (insn->addr_bytes) { + case 2: + insn->moffset1.value = get_next(short, insn); + insn->moffset1.nbytes = 2; + break; + case 4: + insn->moffset1.value = get_next(int, insn); + insn->moffset1.nbytes = 4; + break; + case 8: + insn->moffset1.value = get_next(int, insn); + insn->moffset1.nbytes = 4; + insn->moffset2.value = get_next(int, insn); + insn->moffset2.nbytes = 4; + break; + default: /* opnd_bytes must be modified manually */ + goto err_out; + } + insn->moffset1.got = insn->moffset2.got = 1; + + return 1; + +err_out: + return 0; +} + +/* Decode imm v32(Iz). Return 0 if failed */ +static int __get_immv32(struct insn *insn) +{ + switch (insn->opnd_bytes) { + case 2: + insn->immediate.value = get_next(short, insn); + insn->immediate.nbytes = 2; + break; + case 4: + case 8: + insn->immediate.value = get_next(int, insn); + insn->immediate.nbytes = 4; + break; + default: /* opnd_bytes must be modified manually */ + goto err_out; + } + + return 1; + +err_out: + return 0; +} + +/* Decode imm v64(Iv/Ov), Return 0 if failed */ +static int __get_immv(struct insn *insn) +{ + switch (insn->opnd_bytes) { + case 2: + insn->immediate1.value = get_next(short, insn); + insn->immediate1.nbytes = 2; + break; + case 4: + insn->immediate1.value = get_next(int, insn); + insn->immediate1.nbytes = 4; + break; + case 8: + insn->immediate1.value = get_next(int, insn); + insn->immediate1.nbytes = 4; + insn->immediate2.value = get_next(int, insn); + insn->immediate2.nbytes = 4; + break; + default: /* opnd_bytes must be modified manually */ + goto err_out; + } + insn->immediate1.got = insn->immediate2.got = 1; + + return 1; +err_out: + return 0; +} + +/* Decode ptr16:16/32(Ap) */ +static int __get_immptr(struct insn *insn) +{ + switch (insn->opnd_bytes) { + case 2: + insn->immediate1.value = get_next(short, insn); + insn->immediate1.nbytes = 2; + break; + case 4: + insn->immediate1.value = get_next(int, insn); + insn->immediate1.nbytes = 4; + break; + case 8: + /* ptr16:64 is not exist (no segment) */ + return 0; + default: /* opnd_bytes must be modified manually */ + goto err_out; + } + insn->immediate2.value = get_next(unsigned short, insn); + insn->immediate2.nbytes = 2; + insn->immediate1.got = insn->immediate2.got = 1; + + return 1; +err_out: + return 0; +} + +/** + * insn_get_immediate() - Get the immediates of instruction + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * displacement bytes. + * Basically, most of immediates are sign-expanded. Unsigned-value can be + * get by bit masking with ((1 << (nbytes * 8)) - 1) + */ +void insn_get_immediate(struct insn *insn) +{ + if (insn->immediate.got) + return; + if (!insn->displacement.got) + insn_get_displacement(insn); + + if (inat_has_moffset(insn->attr)) { + if (!__get_moffset(insn)) + goto err_out; + goto done; + } + + if (!inat_has_immediate(insn->attr)) + /* no immediates */ + goto done; + + switch (inat_immediate_size(insn->attr)) { + case INAT_IMM_BYTE: + insn->immediate.value = get_next(char, insn); + insn->immediate.nbytes = 1; + break; + case INAT_IMM_WORD: + insn->immediate.value = get_next(short, insn); + insn->immediate.nbytes = 2; + break; + case INAT_IMM_DWORD: + insn->immediate.value = get_next(int, insn); + insn->immediate.nbytes = 4; + break; + case INAT_IMM_QWORD: + insn->immediate1.value = get_next(int, insn); + insn->immediate1.nbytes = 4; + insn->immediate2.value = get_next(int, insn); + insn->immediate2.nbytes = 4; + break; + case INAT_IMM_PTR: + if (!__get_immptr(insn)) + goto err_out; + break; + case INAT_IMM_VWORD32: + if (!__get_immv32(insn)) + goto err_out; + break; + case INAT_IMM_VWORD: + if (!__get_immv(insn)) + goto err_out; + break; + default: + /* Here, insn must have an immediate, but failed */ + goto err_out; + } + if (inat_has_second_immediate(insn->attr)) { + insn->immediate2.value = get_next(char, insn); + insn->immediate2.nbytes = 1; + } +done: + insn->immediate.got = 1; + +err_out: + return; +} + +/** + * insn_get_length() - Get the length of instruction + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * immediates bytes. + */ +void insn_get_length(struct insn *insn) +{ + if (insn->length) + return; + if (!insn->immediate.got) + insn_get_immediate(insn); + insn->length = (unsigned char)((unsigned long)insn->next_byte + - (unsigned long)insn->kaddr); +} diff --git a/tools/objtool/arch/x86/insn/insn.h b/tools/objtool/arch/x86/insn/insn.h new file mode 100644 index 000000000000..dd12da0f4593 --- /dev/null +++ b/tools/objtool/arch/x86/insn/insn.h @@ -0,0 +1,201 @@ +#ifndef _ASM_X86_INSN_H +#define _ASM_X86_INSN_H +/* + * x86 instruction analysis + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2009 + */ + +/* insn_attr_t is defined in inat.h */ +#include "inat.h" + +struct insn_field { + union { + insn_value_t value; + insn_byte_t bytes[4]; + }; + /* !0 if we've run insn_get_xxx() for this field */ + unsigned char got; + unsigned char nbytes; +}; + +struct insn { + struct insn_field prefixes; /* + * Prefixes + * prefixes.bytes[3]: last prefix + */ + struct insn_field rex_prefix; /* REX prefix */ + struct insn_field vex_prefix; /* VEX prefix */ + struct insn_field opcode; /* + * opcode.bytes[0]: opcode1 + * opcode.bytes[1]: opcode2 + * opcode.bytes[2]: opcode3 + */ + struct insn_field modrm; + struct insn_field sib; + struct insn_field displacement; + union { + struct insn_field immediate; + struct insn_field moffset1; /* for 64bit MOV */ + struct insn_field immediate1; /* for 64bit imm or off16/32 */ + }; + union { + struct insn_field moffset2; /* for 64bit MOV */ + struct insn_field immediate2; /* for 64bit imm or seg16 */ + }; + + insn_attr_t attr; + unsigned char opnd_bytes; + unsigned char addr_bytes; + unsigned char length; + unsigned char x86_64; + + const insn_byte_t *kaddr; /* kernel address of insn to analyze */ + const insn_byte_t *end_kaddr; /* kernel address of last insn in buffer */ + const insn_byte_t *next_byte; +}; + +#define MAX_INSN_SIZE 15 + +#define X86_MODRM_MOD(modrm) (((modrm) & 0xc0) >> 6) +#define X86_MODRM_REG(modrm) (((modrm) & 0x38) >> 3) +#define X86_MODRM_RM(modrm) ((modrm) & 0x07) + +#define X86_SIB_SCALE(sib) (((sib) & 0xc0) >> 6) +#define X86_SIB_INDEX(sib) (((sib) & 0x38) >> 3) +#define X86_SIB_BASE(sib) ((sib) & 0x07) + +#define X86_REX_W(rex) ((rex) & 8) +#define X86_REX_R(rex) ((rex) & 4) +#define X86_REX_X(rex) ((rex) & 2) +#define X86_REX_B(rex) ((rex) & 1) + +/* VEX bit flags */ +#define X86_VEX_W(vex) ((vex) & 0x80) /* VEX3 Byte2 */ +#define X86_VEX_R(vex) ((vex) & 0x80) /* VEX2/3 Byte1 */ +#define X86_VEX_X(vex) ((vex) & 0x40) /* VEX3 Byte1 */ +#define X86_VEX_B(vex) ((vex) & 0x20) /* VEX3 Byte1 */ +#define X86_VEX_L(vex) ((vex) & 0x04) /* VEX3 Byte2, VEX2 Byte1 */ +/* VEX bit fields */ +#define X86_VEX3_M(vex) ((vex) & 0x1f) /* VEX3 Byte1 */ +#define X86_VEX2_M 1 /* VEX2.M always 1 */ +#define X86_VEX_V(vex) (((vex) & 0x78) >> 3) /* VEX3 Byte2, VEX2 Byte1 */ +#define X86_VEX_P(vex) ((vex) & 0x03) /* VEX3 Byte2, VEX2 Byte1 */ +#define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */ + +extern void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64); +extern void insn_get_prefixes(struct insn *insn); +extern void insn_get_opcode(struct insn *insn); +extern void insn_get_modrm(struct insn *insn); +extern void insn_get_sib(struct insn *insn); +extern void insn_get_displacement(struct insn *insn); +extern void insn_get_immediate(struct insn *insn); +extern void insn_get_length(struct insn *insn); + +/* Attribute will be determined after getting ModRM (for opcode groups) */ +static inline void insn_get_attribute(struct insn *insn) +{ + insn_get_modrm(insn); +} + +/* Instruction uses RIP-relative addressing */ +extern int insn_rip_relative(struct insn *insn); + +/* Init insn for kernel text */ +static inline void kernel_insn_init(struct insn *insn, + const void *kaddr, int buf_len) +{ +#ifdef CONFIG_X86_64 + insn_init(insn, kaddr, buf_len, 1); +#else /* CONFIG_X86_32 */ + insn_init(insn, kaddr, buf_len, 0); +#endif +} + +static inline int insn_is_avx(struct insn *insn) +{ + if (!insn->prefixes.got) + insn_get_prefixes(insn); + return (insn->vex_prefix.value != 0); +} + +/* Ensure this instruction is decoded completely */ +static inline int insn_complete(struct insn *insn) +{ + return insn->opcode.got && insn->modrm.got && insn->sib.got && + insn->displacement.got && insn->immediate.got; +} + +static inline insn_byte_t insn_vex_m_bits(struct insn *insn) +{ + if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ + return X86_VEX2_M; + else + return X86_VEX3_M(insn->vex_prefix.bytes[1]); +} + +static inline insn_byte_t insn_vex_p_bits(struct insn *insn) +{ + if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ + return X86_VEX_P(insn->vex_prefix.bytes[1]); + else + return X86_VEX_P(insn->vex_prefix.bytes[2]); +} + +/* Get the last prefix id from last prefix or VEX prefix */ +static inline int insn_last_prefix_id(struct insn *insn) +{ + if (insn_is_avx(insn)) + return insn_vex_p_bits(insn); /* VEX_p is a SIMD prefix id */ + + if (insn->prefixes.bytes[3]) + return inat_get_last_prefix_id(insn->prefixes.bytes[3]); + + return 0; +} + +/* Offset of each field from kaddr */ +static inline int insn_offset_rex_prefix(struct insn *insn) +{ + return insn->prefixes.nbytes; +} +static inline int insn_offset_vex_prefix(struct insn *insn) +{ + return insn_offset_rex_prefix(insn) + insn->rex_prefix.nbytes; +} +static inline int insn_offset_opcode(struct insn *insn) +{ + return insn_offset_vex_prefix(insn) + insn->vex_prefix.nbytes; +} +static inline int insn_offset_modrm(struct insn *insn) +{ + return insn_offset_opcode(insn) + insn->opcode.nbytes; +} +static inline int insn_offset_sib(struct insn *insn) +{ + return insn_offset_modrm(insn) + insn->modrm.nbytes; +} +static inline int insn_offset_displacement(struct insn *insn) +{ + return insn_offset_sib(insn) + insn->sib.nbytes; +} +static inline int insn_offset_immediate(struct insn *insn) +{ + return insn_offset_displacement(insn) + insn->displacement.nbytes; +} + +#endif /* _ASM_X86_INSN_H */ diff --git a/tools/objtool/arch/x86/insn/x86-opcode-map.txt b/tools/objtool/arch/x86/insn/x86-opcode-map.txt new file mode 100644 index 000000000000..d388de72eaca --- /dev/null +++ b/tools/objtool/arch/x86/insn/x86-opcode-map.txt @@ -0,0 +1,984 @@ +# x86 Opcode Maps +# +# This is (mostly) based on following documentations. +# - Intel(R) 64 and IA-32 Architectures Software Developer's Manual Vol.2C +# (#326018-047US, June 2013) +# +# +# Table: table-name +# Referrer: escaped-name +# AVXcode: avx-code +# opcode: mnemonic|GrpXXX [operand1[,operand2...]] [(extra1)[,(extra2)...] [| 2nd-mnemonic ...] +# (or) +# opcode: escape # escaped-name +# EndTable +# +# +# GrpTable: GrpXXX +# reg: mnemonic [operand1[,operand2...]] [(extra1)[,(extra2)...] [| 2nd-mnemonic ...] +# EndTable +# +# AVX Superscripts +# (v): this opcode requires VEX prefix. +# (v1): this opcode only supports 128bit VEX. +# +# Last Prefix Superscripts +# - (66): the last prefix is 0x66 +# - (F3): the last prefix is 0xF3 +# - (F2): the last prefix is 0xF2 +# - (!F3) : the last prefix is not 0xF3 (including non-last prefix case) +# - (66&F2): Both 0x66 and 0xF2 prefixes are specified. + +Table: one byte opcode +Referrer: +AVXcode: +# 0x00 - 0x0f +00: ADD Eb,Gb +01: ADD Ev,Gv +02: ADD Gb,Eb +03: ADD Gv,Ev +04: ADD AL,Ib +05: ADD rAX,Iz +06: PUSH ES (i64) +07: POP ES (i64) +08: OR Eb,Gb +09: OR Ev,Gv +0a: OR Gb,Eb +0b: OR Gv,Ev +0c: OR AL,Ib +0d: OR rAX,Iz +0e: PUSH CS (i64) +0f: escape # 2-byte escape +# 0x10 - 0x1f +10: ADC Eb,Gb +11: ADC Ev,Gv +12: ADC Gb,Eb +13: ADC Gv,Ev +14: ADC AL,Ib +15: ADC rAX,Iz +16: PUSH SS (i64) +17: POP SS (i64) +18: SBB Eb,Gb +19: SBB Ev,Gv +1a: SBB Gb,Eb +1b: SBB Gv,Ev +1c: SBB AL,Ib +1d: SBB rAX,Iz +1e: PUSH DS (i64) +1f: POP DS (i64) +# 0x20 - 0x2f +20: AND Eb,Gb +21: AND Ev,Gv +22: AND Gb,Eb +23: AND Gv,Ev +24: AND AL,Ib +25: AND rAx,Iz +26: SEG=ES (Prefix) +27: DAA (i64) +28: SUB Eb,Gb +29: SUB Ev,Gv +2a: SUB Gb,Eb +2b: SUB Gv,Ev +2c: SUB AL,Ib +2d: SUB rAX,Iz +2e: SEG=CS (Prefix) +2f: DAS (i64) +# 0x30 - 0x3f +30: XOR Eb,Gb +31: XOR Ev,Gv +32: XOR Gb,Eb +33: XOR Gv,Ev +34: XOR AL,Ib +35: XOR rAX,Iz +36: SEG=SS (Prefix) +37: AAA (i64) +38: CMP Eb,Gb +39: CMP Ev,Gv +3a: CMP Gb,Eb +3b: CMP Gv,Ev +3c: CMP AL,Ib +3d: CMP rAX,Iz +3e: SEG=DS (Prefix) +3f: AAS (i64) +# 0x40 - 0x4f +40: INC eAX (i64) | REX (o64) +41: INC eCX (i64) | REX.B (o64) +42: INC eDX (i64) | REX.X (o64) +43: INC eBX (i64) | REX.XB (o64) +44: INC eSP (i64) | REX.R (o64) +45: INC eBP (i64) | REX.RB (o64) +46: INC eSI (i64) | REX.RX (o64) +47: INC eDI (i64) | REX.RXB (o64) +48: DEC eAX (i64) | REX.W (o64) +49: DEC eCX (i64) | REX.WB (o64) +4a: DEC eDX (i64) | REX.WX (o64) +4b: DEC eBX (i64) | REX.WXB (o64) +4c: DEC eSP (i64) | REX.WR (o64) +4d: DEC eBP (i64) | REX.WRB (o64) +4e: DEC eSI (i64) | REX.WRX (o64) +4f: DEC eDI (i64) | REX.WRXB (o64) +# 0x50 - 0x5f +50: PUSH rAX/r8 (d64) +51: PUSH rCX/r9 (d64) +52: PUSH rDX/r10 (d64) +53: PUSH rBX/r11 (d64) +54: PUSH rSP/r12 (d64) +55: PUSH rBP/r13 (d64) +56: PUSH rSI/r14 (d64) +57: PUSH rDI/r15 (d64) +58: POP rAX/r8 (d64) +59: POP rCX/r9 (d64) +5a: POP rDX/r10 (d64) +5b: POP rBX/r11 (d64) +5c: POP rSP/r12 (d64) +5d: POP rBP/r13 (d64) +5e: POP rSI/r14 (d64) +5f: POP rDI/r15 (d64) +# 0x60 - 0x6f +60: PUSHA/PUSHAD (i64) +61: POPA/POPAD (i64) +62: BOUND Gv,Ma (i64) +63: ARPL Ew,Gw (i64) | MOVSXD Gv,Ev (o64) +64: SEG=FS (Prefix) +65: SEG=GS (Prefix) +66: Operand-Size (Prefix) +67: Address-Size (Prefix) +68: PUSH Iz (d64) +69: IMUL Gv,Ev,Iz +6a: PUSH Ib (d64) +6b: IMUL Gv,Ev,Ib +6c: INS/INSB Yb,DX +6d: INS/INSW/INSD Yz,DX +6e: OUTS/OUTSB DX,Xb +6f: OUTS/OUTSW/OUTSD DX,Xz +# 0x70 - 0x7f +70: JO Jb +71: JNO Jb +72: JB/JNAE/JC Jb +73: JNB/JAE/JNC Jb +74: JZ/JE Jb +75: JNZ/JNE Jb +76: JBE/JNA Jb +77: JNBE/JA Jb +78: JS Jb +79: JNS Jb +7a: JP/JPE Jb +7b: JNP/JPO Jb +7c: JL/JNGE Jb +7d: JNL/JGE Jb +7e: JLE/JNG Jb +7f: JNLE/JG Jb +# 0x80 - 0x8f +80: Grp1 Eb,Ib (1A) +81: Grp1 Ev,Iz (1A) +82: Grp1 Eb,Ib (1A),(i64) +83: Grp1 Ev,Ib (1A) +84: TEST Eb,Gb +85: TEST Ev,Gv +86: XCHG Eb,Gb +87: XCHG Ev,Gv +88: MOV Eb,Gb +89: MOV Ev,Gv +8a: MOV Gb,Eb +8b: MOV Gv,Ev +8c: MOV Ev,Sw +8d: LEA Gv,M +8e: MOV Sw,Ew +8f: Grp1A (1A) | POP Ev (d64) +# 0x90 - 0x9f +90: NOP | PAUSE (F3) | XCHG r8,rAX +91: XCHG rCX/r9,rAX +92: XCHG rDX/r10,rAX +93: XCHG rBX/r11,rAX +94: XCHG rSP/r12,rAX +95: XCHG rBP/r13,rAX +96: XCHG rSI/r14,rAX +97: XCHG rDI/r15,rAX +98: CBW/CWDE/CDQE +99: CWD/CDQ/CQO +9a: CALLF Ap (i64) +9b: FWAIT/WAIT +9c: PUSHF/D/Q Fv (d64) +9d: POPF/D/Q Fv (d64) +9e: SAHF +9f: LAHF +# 0xa0 - 0xaf +a0: MOV AL,Ob +a1: MOV rAX,Ov +a2: MOV Ob,AL +a3: MOV Ov,rAX +a4: MOVS/B Yb,Xb +a5: MOVS/W/D/Q Yv,Xv +a6: CMPS/B Xb,Yb +a7: CMPS/W/D Xv,Yv +a8: TEST AL,Ib +a9: TEST rAX,Iz +aa: STOS/B Yb,AL +ab: STOS/W/D/Q Yv,rAX +ac: LODS/B AL,Xb +ad: LODS/W/D/Q rAX,Xv +ae: SCAS/B AL,Yb +# Note: The May 2011 Intel manual shows Xv for the second parameter of the +# next instruction but Yv is correct +af: SCAS/W/D/Q rAX,Yv +# 0xb0 - 0xbf +b0: MOV AL/R8L,Ib +b1: MOV CL/R9L,Ib +b2: MOV DL/R10L,Ib +b3: MOV BL/R11L,Ib +b4: MOV AH/R12L,Ib +b5: MOV CH/R13L,Ib +b6: MOV DH/R14L,Ib +b7: MOV BH/R15L,Ib +b8: MOV rAX/r8,Iv +b9: MOV rCX/r9,Iv +ba: MOV rDX/r10,Iv +bb: MOV rBX/r11,Iv +bc: MOV rSP/r12,Iv +bd: MOV rBP/r13,Iv +be: MOV rSI/r14,Iv +bf: MOV rDI/r15,Iv +# 0xc0 - 0xcf +c0: Grp2 Eb,Ib (1A) +c1: Grp2 Ev,Ib (1A) +c2: RETN Iw (f64) +c3: RETN +c4: LES Gz,Mp (i64) | VEX+2byte (Prefix) +c5: LDS Gz,Mp (i64) | VEX+1byte (Prefix) +c6: Grp11A Eb,Ib (1A) +c7: Grp11B Ev,Iz (1A) +c8: ENTER Iw,Ib +c9: LEAVE (d64) +ca: RETF Iw +cb: RETF +cc: INT3 +cd: INT Ib +ce: INTO (i64) +cf: IRET/D/Q +# 0xd0 - 0xdf +d0: Grp2 Eb,1 (1A) +d1: Grp2 Ev,1 (1A) +d2: Grp2 Eb,CL (1A) +d3: Grp2 Ev,CL (1A) +d4: AAM Ib (i64) +d5: AAD Ib (i64) +d6: +d7: XLAT/XLATB +d8: ESC +d9: ESC +da: ESC +db: ESC +dc: ESC +dd: ESC +de: ESC +df: ESC +# 0xe0 - 0xef +# Note: "forced64" is Intel CPU behavior: they ignore 0x66 prefix +# in 64-bit mode. AMD CPUs accept 0x66 prefix, it causes RIP truncation +# to 16 bits. In 32-bit mode, 0x66 is accepted by both Intel and AMD. +e0: LOOPNE/LOOPNZ Jb (f64) +e1: LOOPE/LOOPZ Jb (f64) +e2: LOOP Jb (f64) +e3: JrCXZ Jb (f64) +e4: IN AL,Ib +e5: IN eAX,Ib +e6: OUT Ib,AL +e7: OUT Ib,eAX +# With 0x66 prefix in 64-bit mode, for AMD CPUs immediate offset +# in "near" jumps and calls is 16-bit. For CALL, +# push of return address is 16-bit wide, RSP is decremented by 2 +# but is not truncated to 16 bits, unlike RIP. +e8: CALL Jz (f64) +e9: JMP-near Jz (f64) +ea: JMP-far Ap (i64) +eb: JMP-short Jb (f64) +ec: IN AL,DX +ed: IN eAX,DX +ee: OUT DX,AL +ef: OUT DX,eAX +# 0xf0 - 0xff +f0: LOCK (Prefix) +f1: +f2: REPNE (Prefix) | XACQUIRE (Prefix) +f3: REP/REPE (Prefix) | XRELEASE (Prefix) +f4: HLT +f5: CMC +f6: Grp3_1 Eb (1A) +f7: Grp3_2 Ev (1A) +f8: CLC +f9: STC +fa: CLI +fb: STI +fc: CLD +fd: STD +fe: Grp4 (1A) +ff: Grp5 (1A) +EndTable + +Table: 2-byte opcode (0x0f) +Referrer: 2-byte escape +AVXcode: 1 +# 0x0f 0x00-0x0f +00: Grp6 (1A) +01: Grp7 (1A) +02: LAR Gv,Ew +03: LSL Gv,Ew +04: +05: SYSCALL (o64) +06: CLTS +07: SYSRET (o64) +08: INVD +09: WBINVD +0a: +0b: UD2 (1B) +0c: +# AMD's prefetch group. Intel supports prefetchw(/1) only. +0d: GrpP +0e: FEMMS +# 3DNow! uses the last imm byte as opcode extension. +0f: 3DNow! Pq,Qq,Ib +# 0x0f 0x10-0x1f +# NOTE: According to Intel SDM opcode map, vmovups and vmovupd has no operands +# but it actually has operands. And also, vmovss and vmovsd only accept 128bit. +# MOVSS/MOVSD has too many forms(3) on SDM. This map just shows a typical form. +# Many AVX instructions lack v1 superscript, according to Intel AVX-Prgramming +# Reference A.1 +10: vmovups Vps,Wps | vmovupd Vpd,Wpd (66) | vmovss Vx,Hx,Wss (F3),(v1) | vmovsd Vx,Hx,Wsd (F2),(v1) +11: vmovups Wps,Vps | vmovupd Wpd,Vpd (66) | vmovss Wss,Hx,Vss (F3),(v1) | vmovsd Wsd,Hx,Vsd (F2),(v1) +12: vmovlps Vq,Hq,Mq (v1) | vmovhlps Vq,Hq,Uq (v1) | vmovlpd Vq,Hq,Mq (66),(v1) | vmovsldup Vx,Wx (F3) | vmovddup Vx,Wx (F2) +13: vmovlps Mq,Vq (v1) | vmovlpd Mq,Vq (66),(v1) +14: vunpcklps Vx,Hx,Wx | vunpcklpd Vx,Hx,Wx (66) +15: vunpckhps Vx,Hx,Wx | vunpckhpd Vx,Hx,Wx (66) +16: vmovhps Vdq,Hq,Mq (v1) | vmovlhps Vdq,Hq,Uq (v1) | vmovhpd Vdq,Hq,Mq (66),(v1) | vmovshdup Vx,Wx (F3) +17: vmovhps Mq,Vq (v1) | vmovhpd Mq,Vq (66),(v1) +18: Grp16 (1A) +19: +# Intel SDM opcode map does not list MPX instructions. For now using Gv for +# bnd registers and Ev for everything else is OK because the instruction +# decoder does not use the information except as an indication that there is +# a ModR/M byte. +1a: BNDCL Gv,Ev (F3) | BNDCU Gv,Ev (F2) | BNDMOV Gv,Ev (66) | BNDLDX Gv,Ev +1b: BNDCN Gv,Ev (F2) | BNDMOV Ev,Gv (66) | BNDMK Gv,Ev (F3) | BNDSTX Ev,Gv +1c: +1d: +1e: +1f: NOP Ev +# 0x0f 0x20-0x2f +20: MOV Rd,Cd +21: MOV Rd,Dd +22: MOV Cd,Rd +23: MOV Dd,Rd +24: +25: +26: +27: +28: vmovaps Vps,Wps | vmovapd Vpd,Wpd (66) +29: vmovaps Wps,Vps | vmovapd Wpd,Vpd (66) +2a: cvtpi2ps Vps,Qpi | cvtpi2pd Vpd,Qpi (66) | vcvtsi2ss Vss,Hss,Ey (F3),(v1) | vcvtsi2sd Vsd,Hsd,Ey (F2),(v1) +2b: vmovntps Mps,Vps | vmovntpd Mpd,Vpd (66) +2c: cvttps2pi Ppi,Wps | cvttpd2pi Ppi,Wpd (66) | vcvttss2si Gy,Wss (F3),(v1) | vcvttsd2si Gy,Wsd (F2),(v1) +2d: cvtps2pi Ppi,Wps | cvtpd2pi Qpi,Wpd (66) | vcvtss2si Gy,Wss (F3),(v1) | vcvtsd2si Gy,Wsd (F2),(v1) +2e: vucomiss Vss,Wss (v1) | vucomisd Vsd,Wsd (66),(v1) +2f: vcomiss Vss,Wss (v1) | vcomisd Vsd,Wsd (66),(v1) +# 0x0f 0x30-0x3f +30: WRMSR +31: RDTSC +32: RDMSR +33: RDPMC +34: SYSENTER +35: SYSEXIT +36: +37: GETSEC +38: escape # 3-byte escape 1 +39: +3a: escape # 3-byte escape 2 +3b: +3c: +3d: +3e: +3f: +# 0x0f 0x40-0x4f +40: CMOVO Gv,Ev +41: CMOVNO Gv,Ev +42: CMOVB/C/NAE Gv,Ev +43: CMOVAE/NB/NC Gv,Ev +44: CMOVE/Z Gv,Ev +45: CMOVNE/NZ Gv,Ev +46: CMOVBE/NA Gv,Ev +47: CMOVA/NBE Gv,Ev +48: CMOVS Gv,Ev +49: CMOVNS Gv,Ev +4a: CMOVP/PE Gv,Ev +4b: CMOVNP/PO Gv,Ev +4c: CMOVL/NGE Gv,Ev +4d: CMOVNL/GE Gv,Ev +4e: CMOVLE/NG Gv,Ev +4f: CMOVNLE/G Gv,Ev +# 0x0f 0x50-0x5f +50: vmovmskps Gy,Ups | vmovmskpd Gy,Upd (66) +51: vsqrtps Vps,Wps | vsqrtpd Vpd,Wpd (66) | vsqrtss Vss,Hss,Wss (F3),(v1) | vsqrtsd Vsd,Hsd,Wsd (F2),(v1) +52: vrsqrtps Vps,Wps | vrsqrtss Vss,Hss,Wss (F3),(v1) +53: vrcpps Vps,Wps | vrcpss Vss,Hss,Wss (F3),(v1) +54: vandps Vps,Hps,Wps | vandpd Vpd,Hpd,Wpd (66) +55: vandnps Vps,Hps,Wps | vandnpd Vpd,Hpd,Wpd (66) +56: vorps Vps,Hps,Wps | vorpd Vpd,Hpd,Wpd (66) +57: vxorps Vps,Hps,Wps | vxorpd Vpd,Hpd,Wpd (66) +58: vaddps Vps,Hps,Wps | vaddpd Vpd,Hpd,Wpd (66) | vaddss Vss,Hss,Wss (F3),(v1) | vaddsd Vsd,Hsd,Wsd (F2),(v1) +59: vmulps Vps,Hps,Wps | vmulpd Vpd,Hpd,Wpd (66) | vmulss Vss,Hss,Wss (F3),(v1) | vmulsd Vsd,Hsd,Wsd (F2),(v1) +5a: vcvtps2pd Vpd,Wps | vcvtpd2ps Vps,Wpd (66) | vcvtss2sd Vsd,Hx,Wss (F3),(v1) | vcvtsd2ss Vss,Hx,Wsd (F2),(v1) +5b: vcvtdq2ps Vps,Wdq | vcvtps2dq Vdq,Wps (66) | vcvttps2dq Vdq,Wps (F3) +5c: vsubps Vps,Hps,Wps | vsubpd Vpd,Hpd,Wpd (66) | vsubss Vss,Hss,Wss (F3),(v1) | vsubsd Vsd,Hsd,Wsd (F2),(v1) +5d: vminps Vps,Hps,Wps | vminpd Vpd,Hpd,Wpd (66) | vminss Vss,Hss,Wss (F3),(v1) | vminsd Vsd,Hsd,Wsd (F2),(v1) +5e: vdivps Vps,Hps,Wps | vdivpd Vpd,Hpd,Wpd (66) | vdivss Vss,Hss,Wss (F3),(v1) | vdivsd Vsd,Hsd,Wsd (F2),(v1) +5f: vmaxps Vps,Hps,Wps | vmaxpd Vpd,Hpd,Wpd (66) | vmaxss Vss,Hss,Wss (F3),(v1) | vmaxsd Vsd,Hsd,Wsd (F2),(v1) +# 0x0f 0x60-0x6f +60: punpcklbw Pq,Qd | vpunpcklbw Vx,Hx,Wx (66),(v1) +61: punpcklwd Pq,Qd | vpunpcklwd Vx,Hx,Wx (66),(v1) +62: punpckldq Pq,Qd | vpunpckldq Vx,Hx,Wx (66),(v1) +63: packsswb Pq,Qq | vpacksswb Vx,Hx,Wx (66),(v1) +64: pcmpgtb Pq,Qq | vpcmpgtb Vx,Hx,Wx (66),(v1) +65: pcmpgtw Pq,Qq | vpcmpgtw Vx,Hx,Wx (66),(v1) +66: pcmpgtd Pq,Qq | vpcmpgtd Vx,Hx,Wx (66),(v1) +67: packuswb Pq,Qq | vpackuswb Vx,Hx,Wx (66),(v1) +68: punpckhbw Pq,Qd | vpunpckhbw Vx,Hx,Wx (66),(v1) +69: punpckhwd Pq,Qd | vpunpckhwd Vx,Hx,Wx (66),(v1) +6a: punpckhdq Pq,Qd | vpunpckhdq Vx,Hx,Wx (66),(v1) +6b: packssdw Pq,Qd | vpackssdw Vx,Hx,Wx (66),(v1) +6c: vpunpcklqdq Vx,Hx,Wx (66),(v1) +6d: vpunpckhqdq Vx,Hx,Wx (66),(v1) +6e: movd/q Pd,Ey | vmovd/q Vy,Ey (66),(v1) +6f: movq Pq,Qq | vmovdqa Vx,Wx (66) | vmovdqu Vx,Wx (F3) +# 0x0f 0x70-0x7f +70: pshufw Pq,Qq,Ib | vpshufd Vx,Wx,Ib (66),(v1) | vpshufhw Vx,Wx,Ib (F3),(v1) | vpshuflw Vx,Wx,Ib (F2),(v1) +71: Grp12 (1A) +72: Grp13 (1A) +73: Grp14 (1A) +74: pcmpeqb Pq,Qq | vpcmpeqb Vx,Hx,Wx (66),(v1) +75: pcmpeqw Pq,Qq | vpcmpeqw Vx,Hx,Wx (66),(v1) +76: pcmpeqd Pq,Qq | vpcmpeqd Vx,Hx,Wx (66),(v1) +# Note: Remove (v), because vzeroall and vzeroupper becomes emms without VEX. +77: emms | vzeroupper | vzeroall +78: VMREAD Ey,Gy +79: VMWRITE Gy,Ey +7a: +7b: +7c: vhaddpd Vpd,Hpd,Wpd (66) | vhaddps Vps,Hps,Wps (F2) +7d: vhsubpd Vpd,Hpd,Wpd (66) | vhsubps Vps,Hps,Wps (F2) +7e: movd/q Ey,Pd | vmovd/q Ey,Vy (66),(v1) | vmovq Vq,Wq (F3),(v1) +7f: movq Qq,Pq | vmovdqa Wx,Vx (66) | vmovdqu Wx,Vx (F3) +# 0x0f 0x80-0x8f +# Note: "forced64" is Intel CPU behavior (see comment about CALL insn). +80: JO Jz (f64) +81: JNO Jz (f64) +82: JB/JC/JNAE Jz (f64) +83: JAE/JNB/JNC Jz (f64) +84: JE/JZ Jz (f64) +85: JNE/JNZ Jz (f64) +86: JBE/JNA Jz (f64) +87: JA/JNBE Jz (f64) +88: JS Jz (f64) +89: JNS Jz (f64) +8a: JP/JPE Jz (f64) +8b: JNP/JPO Jz (f64) +8c: JL/JNGE Jz (f64) +8d: JNL/JGE Jz (f64) +8e: JLE/JNG Jz (f64) +8f: JNLE/JG Jz (f64) +# 0x0f 0x90-0x9f +90: SETO Eb +91: SETNO Eb +92: SETB/C/NAE Eb +93: SETAE/NB/NC Eb +94: SETE/Z Eb +95: SETNE/NZ Eb +96: SETBE/NA Eb +97: SETA/NBE Eb +98: SETS Eb +99: SETNS Eb +9a: SETP/PE Eb +9b: SETNP/PO Eb +9c: SETL/NGE Eb +9d: SETNL/GE Eb +9e: SETLE/NG Eb +9f: SETNLE/G Eb +# 0x0f 0xa0-0xaf +a0: PUSH FS (d64) +a1: POP FS (d64) +a2: CPUID +a3: BT Ev,Gv +a4: SHLD Ev,Gv,Ib +a5: SHLD Ev,Gv,CL +a6: GrpPDLK +a7: GrpRNG +a8: PUSH GS (d64) +a9: POP GS (d64) +aa: RSM +ab: BTS Ev,Gv +ac: SHRD Ev,Gv,Ib +ad: SHRD Ev,Gv,CL +ae: Grp15 (1A),(1C) +af: IMUL Gv,Ev +# 0x0f 0xb0-0xbf +b0: CMPXCHG Eb,Gb +b1: CMPXCHG Ev,Gv +b2: LSS Gv,Mp +b3: BTR Ev,Gv +b4: LFS Gv,Mp +b5: LGS Gv,Mp +b6: MOVZX Gv,Eb +b7: MOVZX Gv,Ew +b8: JMPE (!F3) | POPCNT Gv,Ev (F3) +b9: Grp10 (1A) +ba: Grp8 Ev,Ib (1A) +bb: BTC Ev,Gv +bc: BSF Gv,Ev (!F3) | TZCNT Gv,Ev (F3) +bd: BSR Gv,Ev (!F3) | LZCNT Gv,Ev (F3) +be: MOVSX Gv,Eb +bf: MOVSX Gv,Ew +# 0x0f 0xc0-0xcf +c0: XADD Eb,Gb +c1: XADD Ev,Gv +c2: vcmpps Vps,Hps,Wps,Ib | vcmppd Vpd,Hpd,Wpd,Ib (66) | vcmpss Vss,Hss,Wss,Ib (F3),(v1) | vcmpsd Vsd,Hsd,Wsd,Ib (F2),(v1) +c3: movnti My,Gy +c4: pinsrw Pq,Ry/Mw,Ib | vpinsrw Vdq,Hdq,Ry/Mw,Ib (66),(v1) +c5: pextrw Gd,Nq,Ib | vpextrw Gd,Udq,Ib (66),(v1) +c6: vshufps Vps,Hps,Wps,Ib | vshufpd Vpd,Hpd,Wpd,Ib (66) +c7: Grp9 (1A) +c8: BSWAP RAX/EAX/R8/R8D +c9: BSWAP RCX/ECX/R9/R9D +ca: BSWAP RDX/EDX/R10/R10D +cb: BSWAP RBX/EBX/R11/R11D +cc: BSWAP RSP/ESP/R12/R12D +cd: BSWAP RBP/EBP/R13/R13D +ce: BSWAP RSI/ESI/R14/R14D +cf: BSWAP RDI/EDI/R15/R15D +# 0x0f 0xd0-0xdf +d0: vaddsubpd Vpd,Hpd,Wpd (66) | vaddsubps Vps,Hps,Wps (F2) +d1: psrlw Pq,Qq | vpsrlw Vx,Hx,Wx (66),(v1) +d2: psrld Pq,Qq | vpsrld Vx,Hx,Wx (66),(v1) +d3: psrlq Pq,Qq | vpsrlq Vx,Hx,Wx (66),(v1) +d4: paddq Pq,Qq | vpaddq Vx,Hx,Wx (66),(v1) +d5: pmullw Pq,Qq | vpmullw Vx,Hx,Wx (66),(v1) +d6: vmovq Wq,Vq (66),(v1) | movq2dq Vdq,Nq (F3) | movdq2q Pq,Uq (F2) +d7: pmovmskb Gd,Nq | vpmovmskb Gd,Ux (66),(v1) +d8: psubusb Pq,Qq | vpsubusb Vx,Hx,Wx (66),(v1) +d9: psubusw Pq,Qq | vpsubusw Vx,Hx,Wx (66),(v1) +da: pminub Pq,Qq | vpminub Vx,Hx,Wx (66),(v1) +db: pand Pq,Qq | vpand Vx,Hx,Wx (66),(v1) +dc: paddusb Pq,Qq | vpaddusb Vx,Hx,Wx (66),(v1) +dd: paddusw Pq,Qq | vpaddusw Vx,Hx,Wx (66),(v1) +de: pmaxub Pq,Qq | vpmaxub Vx,Hx,Wx (66),(v1) +df: pandn Pq,Qq | vpandn Vx,Hx,Wx (66),(v1) +# 0x0f 0xe0-0xef +e0: pavgb Pq,Qq | vpavgb Vx,Hx,Wx (66),(v1) +e1: psraw Pq,Qq | vpsraw Vx,Hx,Wx (66),(v1) +e2: psrad Pq,Qq | vpsrad Vx,Hx,Wx (66),(v1) +e3: pavgw Pq,Qq | vpavgw Vx,Hx,Wx (66),(v1) +e4: pmulhuw Pq,Qq | vpmulhuw Vx,Hx,Wx (66),(v1) +e5: pmulhw Pq,Qq | vpmulhw Vx,Hx,Wx (66),(v1) +e6: vcvttpd2dq Vx,Wpd (66) | vcvtdq2pd Vx,Wdq (F3) | vcvtpd2dq Vx,Wpd (F2) +e7: movntq Mq,Pq | vmovntdq Mx,Vx (66) +e8: psubsb Pq,Qq | vpsubsb Vx,Hx,Wx (66),(v1) +e9: psubsw Pq,Qq | vpsubsw Vx,Hx,Wx (66),(v1) +ea: pminsw Pq,Qq | vpminsw Vx,Hx,Wx (66),(v1) +eb: por Pq,Qq | vpor Vx,Hx,Wx (66),(v1) +ec: paddsb Pq,Qq | vpaddsb Vx,Hx,Wx (66),(v1) +ed: paddsw Pq,Qq | vpaddsw Vx,Hx,Wx (66),(v1) +ee: pmaxsw Pq,Qq | vpmaxsw Vx,Hx,Wx (66),(v1) +ef: pxor Pq,Qq | vpxor Vx,Hx,Wx (66),(v1) +# 0x0f 0xf0-0xff +f0: vlddqu Vx,Mx (F2) +f1: psllw Pq,Qq | vpsllw Vx,Hx,Wx (66),(v1) +f2: pslld Pq,Qq | vpslld Vx,Hx,Wx (66),(v1) +f3: psllq Pq,Qq | vpsllq Vx,Hx,Wx (66),(v1) +f4: pmuludq Pq,Qq | vpmuludq Vx,Hx,Wx (66),(v1) +f5: pmaddwd Pq,Qq | vpmaddwd Vx,Hx,Wx (66),(v1) +f6: psadbw Pq,Qq | vpsadbw Vx,Hx,Wx (66),(v1) +f7: maskmovq Pq,Nq | vmaskmovdqu Vx,Ux (66),(v1) +f8: psubb Pq,Qq | vpsubb Vx,Hx,Wx (66),(v1) +f9: psubw Pq,Qq | vpsubw Vx,Hx,Wx (66),(v1) +fa: psubd Pq,Qq | vpsubd Vx,Hx,Wx (66),(v1) +fb: psubq Pq,Qq | vpsubq Vx,Hx,Wx (66),(v1) +fc: paddb Pq,Qq | vpaddb Vx,Hx,Wx (66),(v1) +fd: paddw Pq,Qq | vpaddw Vx,Hx,Wx (66),(v1) +fe: paddd Pq,Qq | vpaddd Vx,Hx,Wx (66),(v1) +ff: +EndTable + +Table: 3-byte opcode 1 (0x0f 0x38) +Referrer: 3-byte escape 1 +AVXcode: 2 +# 0x0f 0x38 0x00-0x0f +00: pshufb Pq,Qq | vpshufb Vx,Hx,Wx (66),(v1) +01: phaddw Pq,Qq | vphaddw Vx,Hx,Wx (66),(v1) +02: phaddd Pq,Qq | vphaddd Vx,Hx,Wx (66),(v1) +03: phaddsw Pq,Qq | vphaddsw Vx,Hx,Wx (66),(v1) +04: pmaddubsw Pq,Qq | vpmaddubsw Vx,Hx,Wx (66),(v1) +05: phsubw Pq,Qq | vphsubw Vx,Hx,Wx (66),(v1) +06: phsubd Pq,Qq | vphsubd Vx,Hx,Wx (66),(v1) +07: phsubsw Pq,Qq | vphsubsw Vx,Hx,Wx (66),(v1) +08: psignb Pq,Qq | vpsignb Vx,Hx,Wx (66),(v1) +09: psignw Pq,Qq | vpsignw Vx,Hx,Wx (66),(v1) +0a: psignd Pq,Qq | vpsignd Vx,Hx,Wx (66),(v1) +0b: pmulhrsw Pq,Qq | vpmulhrsw Vx,Hx,Wx (66),(v1) +0c: vpermilps Vx,Hx,Wx (66),(v) +0d: vpermilpd Vx,Hx,Wx (66),(v) +0e: vtestps Vx,Wx (66),(v) +0f: vtestpd Vx,Wx (66),(v) +# 0x0f 0x38 0x10-0x1f +10: pblendvb Vdq,Wdq (66) +11: +12: +13: vcvtph2ps Vx,Wx,Ib (66),(v) +14: blendvps Vdq,Wdq (66) +15: blendvpd Vdq,Wdq (66) +16: vpermps Vqq,Hqq,Wqq (66),(v) +17: vptest Vx,Wx (66) +18: vbroadcastss Vx,Wd (66),(v) +19: vbroadcastsd Vqq,Wq (66),(v) +1a: vbroadcastf128 Vqq,Mdq (66),(v) +1b: +1c: pabsb Pq,Qq | vpabsb Vx,Wx (66),(v1) +1d: pabsw Pq,Qq | vpabsw Vx,Wx (66),(v1) +1e: pabsd Pq,Qq | vpabsd Vx,Wx (66),(v1) +1f: +# 0x0f 0x38 0x20-0x2f +20: vpmovsxbw Vx,Ux/Mq (66),(v1) +21: vpmovsxbd Vx,Ux/Md (66),(v1) +22: vpmovsxbq Vx,Ux/Mw (66),(v1) +23: vpmovsxwd Vx,Ux/Mq (66),(v1) +24: vpmovsxwq Vx,Ux/Md (66),(v1) +25: vpmovsxdq Vx,Ux/Mq (66),(v1) +26: +27: +28: vpmuldq Vx,Hx,Wx (66),(v1) +29: vpcmpeqq Vx,Hx,Wx (66),(v1) +2a: vmovntdqa Vx,Mx (66),(v1) +2b: vpackusdw Vx,Hx,Wx (66),(v1) +2c: vmaskmovps Vx,Hx,Mx (66),(v) +2d: vmaskmovpd Vx,Hx,Mx (66),(v) +2e: vmaskmovps Mx,Hx,Vx (66),(v) +2f: vmaskmovpd Mx,Hx,Vx (66),(v) +# 0x0f 0x38 0x30-0x3f +30: vpmovzxbw Vx,Ux/Mq (66),(v1) +31: vpmovzxbd Vx,Ux/Md (66),(v1) +32: vpmovzxbq Vx,Ux/Mw (66),(v1) +33: vpmovzxwd Vx,Ux/Mq (66),(v1) +34: vpmovzxwq Vx,Ux/Md (66),(v1) +35: vpmovzxdq Vx,Ux/Mq (66),(v1) +36: vpermd Vqq,Hqq,Wqq (66),(v) +37: vpcmpgtq Vx,Hx,Wx (66),(v1) +38: vpminsb Vx,Hx,Wx (66),(v1) +39: vpminsd Vx,Hx,Wx (66),(v1) +3a: vpminuw Vx,Hx,Wx (66),(v1) +3b: vpminud Vx,Hx,Wx (66),(v1) +3c: vpmaxsb Vx,Hx,Wx (66),(v1) +3d: vpmaxsd Vx,Hx,Wx (66),(v1) +3e: vpmaxuw Vx,Hx,Wx (66),(v1) +3f: vpmaxud Vx,Hx,Wx (66),(v1) +# 0x0f 0x38 0x40-0x8f +40: vpmulld Vx,Hx,Wx (66),(v1) +41: vphminposuw Vdq,Wdq (66),(v1) +42: +43: +44: +45: vpsrlvd/q Vx,Hx,Wx (66),(v) +46: vpsravd Vx,Hx,Wx (66),(v) +47: vpsllvd/q Vx,Hx,Wx (66),(v) +# Skip 0x48-0x57 +58: vpbroadcastd Vx,Wx (66),(v) +59: vpbroadcastq Vx,Wx (66),(v) +5a: vbroadcasti128 Vqq,Mdq (66),(v) +# Skip 0x5b-0x77 +78: vpbroadcastb Vx,Wx (66),(v) +79: vpbroadcastw Vx,Wx (66),(v) +# Skip 0x7a-0x7f +80: INVEPT Gy,Mdq (66) +81: INVPID Gy,Mdq (66) +82: INVPCID Gy,Mdq (66) +8c: vpmaskmovd/q Vx,Hx,Mx (66),(v) +8e: vpmaskmovd/q Mx,Vx,Hx (66),(v) +# 0x0f 0x38 0x90-0xbf (FMA) +90: vgatherdd/q Vx,Hx,Wx (66),(v) +91: vgatherqd/q Vx,Hx,Wx (66),(v) +92: vgatherdps/d Vx,Hx,Wx (66),(v) +93: vgatherqps/d Vx,Hx,Wx (66),(v) +94: +95: +96: vfmaddsub132ps/d Vx,Hx,Wx (66),(v) +97: vfmsubadd132ps/d Vx,Hx,Wx (66),(v) +98: vfmadd132ps/d Vx,Hx,Wx (66),(v) +99: vfmadd132ss/d Vx,Hx,Wx (66),(v),(v1) +9a: vfmsub132ps/d Vx,Hx,Wx (66),(v) +9b: vfmsub132ss/d Vx,Hx,Wx (66),(v),(v1) +9c: vfnmadd132ps/d Vx,Hx,Wx (66),(v) +9d: vfnmadd132ss/d Vx,Hx,Wx (66),(v),(v1) +9e: vfnmsub132ps/d Vx,Hx,Wx (66),(v) +9f: vfnmsub132ss/d Vx,Hx,Wx (66),(v),(v1) +a6: vfmaddsub213ps/d Vx,Hx,Wx (66),(v) +a7: vfmsubadd213ps/d Vx,Hx,Wx (66),(v) +a8: vfmadd213ps/d Vx,Hx,Wx (66),(v) +a9: vfmadd213ss/d Vx,Hx,Wx (66),(v),(v1) +aa: vfmsub213ps/d Vx,Hx,Wx (66),(v) +ab: vfmsub213ss/d Vx,Hx,Wx (66),(v),(v1) +ac: vfnmadd213ps/d Vx,Hx,Wx (66),(v) +ad: vfnmadd213ss/d Vx,Hx,Wx (66),(v),(v1) +ae: vfnmsub213ps/d Vx,Hx,Wx (66),(v) +af: vfnmsub213ss/d Vx,Hx,Wx (66),(v),(v1) +b6: vfmaddsub231ps/d Vx,Hx,Wx (66),(v) +b7: vfmsubadd231ps/d Vx,Hx,Wx (66),(v) +b8: vfmadd231ps/d Vx,Hx,Wx (66),(v) +b9: vfmadd231ss/d Vx,Hx,Wx (66),(v),(v1) +ba: vfmsub231ps/d Vx,Hx,Wx (66),(v) +bb: vfmsub231ss/d Vx,Hx,Wx (66),(v),(v1) +bc: vfnmadd231ps/d Vx,Hx,Wx (66),(v) +bd: vfnmadd231ss/d Vx,Hx,Wx (66),(v),(v1) +be: vfnmsub231ps/d Vx,Hx,Wx (66),(v) +bf: vfnmsub231ss/d Vx,Hx,Wx (66),(v),(v1) +# 0x0f 0x38 0xc0-0xff +c8: sha1nexte Vdq,Wdq +c9: sha1msg1 Vdq,Wdq +ca: sha1msg2 Vdq,Wdq +cb: sha256rnds2 Vdq,Wdq +cc: sha256msg1 Vdq,Wdq +cd: sha256msg2 Vdq,Wdq +db: VAESIMC Vdq,Wdq (66),(v1) +dc: VAESENC Vdq,Hdq,Wdq (66),(v1) +dd: VAESENCLAST Vdq,Hdq,Wdq (66),(v1) +de: VAESDEC Vdq,Hdq,Wdq (66),(v1) +df: VAESDECLAST Vdq,Hdq,Wdq (66),(v1) +f0: MOVBE Gy,My | MOVBE Gw,Mw (66) | CRC32 Gd,Eb (F2) | CRC32 Gd,Eb (66&F2) +f1: MOVBE My,Gy | MOVBE Mw,Gw (66) | CRC32 Gd,Ey (F2) | CRC32 Gd,Ew (66&F2) +f2: ANDN Gy,By,Ey (v) +f3: Grp17 (1A) +f5: BZHI Gy,Ey,By (v) | PEXT Gy,By,Ey (F3),(v) | PDEP Gy,By,Ey (F2),(v) +f6: ADCX Gy,Ey (66) | ADOX Gy,Ey (F3) | MULX By,Gy,rDX,Ey (F2),(v) +f7: BEXTR Gy,Ey,By (v) | SHLX Gy,Ey,By (66),(v) | SARX Gy,Ey,By (F3),(v) | SHRX Gy,Ey,By (F2),(v) +EndTable + +Table: 3-byte opcode 2 (0x0f 0x3a) +Referrer: 3-byte escape 2 +AVXcode: 3 +# 0x0f 0x3a 0x00-0xff +00: vpermq Vqq,Wqq,Ib (66),(v) +01: vpermpd Vqq,Wqq,Ib (66),(v) +02: vpblendd Vx,Hx,Wx,Ib (66),(v) +03: +04: vpermilps Vx,Wx,Ib (66),(v) +05: vpermilpd Vx,Wx,Ib (66),(v) +06: vperm2f128 Vqq,Hqq,Wqq,Ib (66),(v) +07: +08: vroundps Vx,Wx,Ib (66) +09: vroundpd Vx,Wx,Ib (66) +0a: vroundss Vss,Wss,Ib (66),(v1) +0b: vroundsd Vsd,Wsd,Ib (66),(v1) +0c: vblendps Vx,Hx,Wx,Ib (66) +0d: vblendpd Vx,Hx,Wx,Ib (66) +0e: vpblendw Vx,Hx,Wx,Ib (66),(v1) +0f: palignr Pq,Qq,Ib | vpalignr Vx,Hx,Wx,Ib (66),(v1) +14: vpextrb Rd/Mb,Vdq,Ib (66),(v1) +15: vpextrw Rd/Mw,Vdq,Ib (66),(v1) +16: vpextrd/q Ey,Vdq,Ib (66),(v1) +17: vextractps Ed,Vdq,Ib (66),(v1) +18: vinsertf128 Vqq,Hqq,Wqq,Ib (66),(v) +19: vextractf128 Wdq,Vqq,Ib (66),(v) +1d: vcvtps2ph Wx,Vx,Ib (66),(v) +20: vpinsrb Vdq,Hdq,Ry/Mb,Ib (66),(v1) +21: vinsertps Vdq,Hdq,Udq/Md,Ib (66),(v1) +22: vpinsrd/q Vdq,Hdq,Ey,Ib (66),(v1) +38: vinserti128 Vqq,Hqq,Wqq,Ib (66),(v) +39: vextracti128 Wdq,Vqq,Ib (66),(v) +40: vdpps Vx,Hx,Wx,Ib (66) +41: vdppd Vdq,Hdq,Wdq,Ib (66),(v1) +42: vmpsadbw Vx,Hx,Wx,Ib (66),(v1) +44: vpclmulqdq Vdq,Hdq,Wdq,Ib (66),(v1) +46: vperm2i128 Vqq,Hqq,Wqq,Ib (66),(v) +4a: vblendvps Vx,Hx,Wx,Lx (66),(v) +4b: vblendvpd Vx,Hx,Wx,Lx (66),(v) +4c: vpblendvb Vx,Hx,Wx,Lx (66),(v1) +60: vpcmpestrm Vdq,Wdq,Ib (66),(v1) +61: vpcmpestri Vdq,Wdq,Ib (66),(v1) +62: vpcmpistrm Vdq,Wdq,Ib (66),(v1) +63: vpcmpistri Vdq,Wdq,Ib (66),(v1) +cc: sha1rnds4 Vdq,Wdq,Ib +df: VAESKEYGEN Vdq,Wdq,Ib (66),(v1) +f0: RORX Gy,Ey,Ib (F2),(v) +EndTable + +GrpTable: Grp1 +0: ADD +1: OR +2: ADC +3: SBB +4: AND +5: SUB +6: XOR +7: CMP +EndTable + +GrpTable: Grp1A +0: POP +EndTable + +GrpTable: Grp2 +0: ROL +1: ROR +2: RCL +3: RCR +4: SHL/SAL +5: SHR +6: +7: SAR +EndTable + +GrpTable: Grp3_1 +0: TEST Eb,Ib +1: +2: NOT Eb +3: NEG Eb +4: MUL AL,Eb +5: IMUL AL,Eb +6: DIV AL,Eb +7: IDIV AL,Eb +EndTable + +GrpTable: Grp3_2 +0: TEST Ev,Iz +1: +2: NOT Ev +3: NEG Ev +4: MUL rAX,Ev +5: IMUL rAX,Ev +6: DIV rAX,Ev +7: IDIV rAX,Ev +EndTable + +GrpTable: Grp4 +0: INC Eb +1: DEC Eb +EndTable + +GrpTable: Grp5 +0: INC Ev +1: DEC Ev +# Note: "forced64" is Intel CPU behavior (see comment about CALL insn). +2: CALLN Ev (f64) +3: CALLF Ep +4: JMPN Ev (f64) +5: JMPF Mp +6: PUSH Ev (d64) +7: +EndTable + +GrpTable: Grp6 +0: SLDT Rv/Mw +1: STR Rv/Mw +2: LLDT Ew +3: LTR Ew +4: VERR Ew +5: VERW Ew +EndTable + +GrpTable: Grp7 +0: SGDT Ms | VMCALL (001),(11B) | VMLAUNCH (010),(11B) | VMRESUME (011),(11B) | VMXOFF (100),(11B) +1: SIDT Ms | MONITOR (000),(11B) | MWAIT (001),(11B) | CLAC (010),(11B) | STAC (011),(11B) +2: LGDT Ms | XGETBV (000),(11B) | XSETBV (001),(11B) | VMFUNC (100),(11B) | XEND (101)(11B) | XTEST (110)(11B) +3: LIDT Ms +4: SMSW Mw/Rv +5: rdpkru (110),(11B) | wrpkru (111),(11B) +6: LMSW Ew +7: INVLPG Mb | SWAPGS (o64),(000),(11B) | RDTSCP (001),(11B) +EndTable + +GrpTable: Grp8 +4: BT +5: BTS +6: BTR +7: BTC +EndTable + +GrpTable: Grp9 +1: CMPXCHG8B/16B Mq/Mdq +3: xrstors +4: xsavec +5: xsaves +6: VMPTRLD Mq | VMCLEAR Mq (66) | VMXON Mq (F3) | RDRAND Rv (11B) +7: VMPTRST Mq | VMPTRST Mq (F3) | RDSEED Rv (11B) +EndTable + +GrpTable: Grp10 +EndTable + +# Grp11A and Grp11B are expressed as Grp11 in Intel SDM +GrpTable: Grp11A +0: MOV Eb,Ib +7: XABORT Ib (000),(11B) +EndTable + +GrpTable: Grp11B +0: MOV Eb,Iz +7: XBEGIN Jz (000),(11B) +EndTable + +GrpTable: Grp12 +2: psrlw Nq,Ib (11B) | vpsrlw Hx,Ux,Ib (66),(11B),(v1) +4: psraw Nq,Ib (11B) | vpsraw Hx,Ux,Ib (66),(11B),(v1) +6: psllw Nq,Ib (11B) | vpsllw Hx,Ux,Ib (66),(11B),(v1) +EndTable + +GrpTable: Grp13 +2: psrld Nq,Ib (11B) | vpsrld Hx,Ux,Ib (66),(11B),(v1) +4: psrad Nq,Ib (11B) | vpsrad Hx,Ux,Ib (66),(11B),(v1) +6: pslld Nq,Ib (11B) | vpslld Hx,Ux,Ib (66),(11B),(v1) +EndTable + +GrpTable: Grp14 +2: psrlq Nq,Ib (11B) | vpsrlq Hx,Ux,Ib (66),(11B),(v1) +3: vpsrldq Hx,Ux,Ib (66),(11B),(v1) +6: psllq Nq,Ib (11B) | vpsllq Hx,Ux,Ib (66),(11B),(v1) +7: vpslldq Hx,Ux,Ib (66),(11B),(v1) +EndTable + +GrpTable: Grp15 +0: fxsave | RDFSBASE Ry (F3),(11B) +1: fxstor | RDGSBASE Ry (F3),(11B) +2: vldmxcsr Md (v1) | WRFSBASE Ry (F3),(11B) +3: vstmxcsr Md (v1) | WRGSBASE Ry (F3),(11B) +4: XSAVE +5: XRSTOR | lfence (11B) +6: XSAVEOPT | clwb (66) | mfence (11B) +7: clflush | clflushopt (66) | sfence (11B) | pcommit (66),(11B) +EndTable + +GrpTable: Grp16 +0: prefetch NTA +1: prefetch T0 +2: prefetch T1 +3: prefetch T2 +EndTable + +GrpTable: Grp17 +1: BLSR By,Ey (v) +2: BLSMSK By,Ey (v) +3: BLSI By,Ey (v) +EndTable + +# AMD's Prefetch Group +GrpTable: GrpP +0: PREFETCH +1: PREFETCHW +EndTable + +GrpTable: GrpPDLK +0: MONTMUL +1: XSHA1 +2: XSHA2 +EndTable + +GrpTable: GrpRNG +0: xstore-rng +1: xcrypt-ecb +2: xcrypt-cbc +4: xcrypt-cfb +5: xcrypt-ofb +EndTable diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c new file mode 100644 index 000000000000..f7e0ebac3fbe --- /dev/null +++ b/tools/objtool/builtin-check.c @@ -0,0 +1,1072 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +/* + * objtool check: + * + * This command analyzes every .o file and ensures the validity of its stack + * trace metadata. It enforces a set of rules on asm code and C inline + * assembly code so that stack traces can be reliable. + * + * For more information, see tools/objtool/Documentation/stack-validation.txt. + */ + +#include +#include + +#include "builtin.h" +#include "elf.h" +#include "special.h" +#include "arch.h" +#include "warn.h" + +#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) + +#define STATE_FP_SAVED 0x1 +#define STATE_FP_SETUP 0x2 +#define STATE_FENTRY 0x4 + +struct instruction { + struct list_head list; + struct section *sec; + unsigned long offset; + unsigned int len, state; + unsigned char type; + unsigned long immediate; + bool alt_group, visited; + struct symbol *call_dest; + struct instruction *jump_dest; + struct list_head alts; +}; + +struct alternative { + struct list_head list; + struct instruction *insn; +}; + +struct objtool_file { + struct elf *elf; + struct list_head insns; +}; + +const char *objname; +static bool nofp; + +static struct instruction *find_instruction(struct objtool_file *file, + struct section *sec, + unsigned long offset) +{ + struct instruction *insn; + + list_for_each_entry(insn, &file->insns, list) + if (insn->sec == sec && insn->offset == offset) + return insn; + + return NULL; +} + +/* + * Check if the function has been manually whitelisted with the + * STACK_FRAME_NON_STANDARD macro, or if it should be automatically whitelisted + * due to its use of a context switching instruction. + */ +static bool ignore_func(struct objtool_file *file, struct symbol *func) +{ + struct section *macro_sec; + struct rela *rela; + struct instruction *insn; + + /* check for STACK_FRAME_NON_STANDARD */ + macro_sec = find_section_by_name(file->elf, "__func_stack_frame_non_standard"); + if (macro_sec && macro_sec->rela) + list_for_each_entry(rela, ¯o_sec->rela->relas, list) + if (rela->sym->sec == func->sec && + rela->addend == func->offset) + return true; + + /* check if it has a context switching instruction */ + insn = find_instruction(file, func->sec, func->offset); + if (!insn) + return false; + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func->offset + func->len) + break; + if (insn->type == INSN_CONTEXT_SWITCH) + return true; + } + + return false; +} + +/* + * This checks to see if the given function is a "noreturn" function. + * + * For global functions which are outside the scope of this object file, we + * have to keep a manual list of them. + * + * For local functions, we have to detect them manually by simply looking for + * the lack of a return instruction. + */ +static bool dead_end_function(struct objtool_file *file, struct symbol *func) +{ + int i; + struct instruction *insn; + bool empty = true; + + /* + * Unfortunately these have to be hard coded because the noreturn + * attribute isn't provided in ELF data. + */ + static const char * const global_noreturns[] = { + "__stack_chk_fail", + "panic", + "do_exit", + "__module_put_and_exit", + "complete_and_exit", + "kvm_spurious_fault", + "__reiserfs_panic", + "lbug_with_loc" + }; + + if (func->bind == STB_WEAK) + return false; + + if (func->bind == STB_GLOBAL) + for (i = 0; i < ARRAY_SIZE(global_noreturns); i++) + if (!strcmp(func->name, global_noreturns[i])) + return true; + + if (!func->sec) + return false; + + insn = find_instruction(file, func->sec, func->offset); + if (!insn) + return false; + + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func->offset + func->len) + break; + + empty = false; + + if (insn->type == INSN_RETURN) + return false; + + if (insn->type == INSN_JUMP_UNCONDITIONAL) { + struct instruction *dest = insn->jump_dest; + struct symbol *dest_func; + + if (!dest) + /* sibling call to another file */ + return false; + + if (dest->sec != func->sec || + dest->offset < func->offset || + dest->offset >= func->offset + func->len) { + /* local sibling call */ + dest_func = find_symbol_by_offset(dest->sec, + dest->offset); + if (!dest_func) + continue; + + return dead_end_function(file, dest_func); + } + } + + if (insn->type == INSN_JUMP_DYNAMIC) + /* sibling call */ + return false; + } + + return !empty; +} + +/* + * Call the arch-specific instruction decoder for all the instructions and add + * them to the global insns list. + */ +static int decode_instructions(struct objtool_file *file) +{ + struct section *sec; + unsigned long offset; + struct instruction *insn; + int ret; + + INIT_LIST_HEAD(&file->insns); + + list_for_each_entry(sec, &file->elf->sections, list) { + + if (!(sec->sh.sh_flags & SHF_EXECINSTR)) + continue; + + for (offset = 0; offset < sec->len; offset += insn->len) { + insn = malloc(sizeof(*insn)); + memset(insn, 0, sizeof(*insn)); + + INIT_LIST_HEAD(&insn->alts); + insn->sec = sec; + insn->offset = offset; + + ret = arch_decode_instruction(file->elf, sec, offset, + sec->len - offset, + &insn->len, &insn->type, + &insn->immediate); + if (ret) + return ret; + + if (!insn->type || insn->type > INSN_LAST) { + WARN_FUNC("invalid instruction type %d", + insn->sec, insn->offset, insn->type); + return -1; + } + + list_add_tail(&insn->list, &file->insns); + } + } + + return 0; +} + +/* + * Warnings shouldn't be reported for ignored functions. + */ +static void get_ignores(struct objtool_file *file) +{ + struct instruction *insn; + struct section *sec; + struct symbol *func; + + list_for_each_entry(sec, &file->elf->sections, list) { + list_for_each_entry(func, &sec->symbols, list) { + if (func->type != STT_FUNC) + continue; + + if (!ignore_func(file, func)) + continue; + + insn = find_instruction(file, sec, func->offset); + if (!insn) + continue; + + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func->offset + func->len) + break; + + insn->visited = true; + } + } + } +} + +/* + * Find the destination instructions for all jumps. + */ +static int get_jump_destinations(struct objtool_file *file) +{ + struct instruction *insn; + struct rela *rela; + struct section *dest_sec; + unsigned long dest_off; + + list_for_each_entry(insn, &file->insns, list) { + if (insn->type != INSN_JUMP_CONDITIONAL && + insn->type != INSN_JUMP_UNCONDITIONAL) + continue; + + /* skip ignores */ + if (insn->visited) + continue; + + rela = find_rela_by_dest_range(insn->sec, insn->offset, + insn->len); + if (!rela) { + dest_sec = insn->sec; + dest_off = insn->offset + insn->len + insn->immediate; + } else if (rela->sym->type == STT_SECTION) { + dest_sec = rela->sym->sec; + dest_off = rela->addend + 4; + } else if (rela->sym->sec->idx) { + dest_sec = rela->sym->sec; + dest_off = rela->sym->sym.st_value + rela->addend + 4; + } else { + /* sibling call */ + insn->jump_dest = 0; + continue; + } + + insn->jump_dest = find_instruction(file, dest_sec, dest_off); + if (!insn->jump_dest) { + + /* + * This is a special case where an alt instruction + * jumps past the end of the section. These are + * handled later in handle_group_alt(). + */ + if (!strcmp(insn->sec->name, ".altinstr_replacement")) + continue; + + WARN_FUNC("can't find jump dest instruction at %s+0x%lx", + insn->sec, insn->offset, dest_sec->name, + dest_off); + return -1; + } + } + + return 0; +} + +/* + * Find the destination instructions for all calls. + */ +static int get_call_destinations(struct objtool_file *file) +{ + struct instruction *insn; + unsigned long dest_off; + struct rela *rela; + + list_for_each_entry(insn, &file->insns, list) { + if (insn->type != INSN_CALL) + continue; + + rela = find_rela_by_dest_range(insn->sec, insn->offset, + insn->len); + if (!rela) { + dest_off = insn->offset + insn->len + insn->immediate; + insn->call_dest = find_symbol_by_offset(insn->sec, + dest_off); + if (!insn->call_dest) { + WARN_FUNC("can't find call dest symbol at offset 0x%lx", + insn->sec, insn->offset, dest_off); + return -1; + } + } else if (rela->sym->type == STT_SECTION) { + insn->call_dest = find_symbol_by_offset(rela->sym->sec, + rela->addend+4); + if (!insn->call_dest || + insn->call_dest->type != STT_FUNC) { + WARN_FUNC("can't find call dest symbol at %s+0x%x", + insn->sec, insn->offset, + rela->sym->sec->name, + rela->addend + 4); + return -1; + } + } else + insn->call_dest = rela->sym; + } + + return 0; +} + +/* + * The .alternatives section requires some extra special care, over and above + * what other special sections require: + * + * 1. Because alternatives are patched in-place, we need to insert a fake jump + * instruction at the end so that validate_branch() skips all the original + * replaced instructions when validating the new instruction path. + * + * 2. An added wrinkle is that the new instruction length might be zero. In + * that case the old instructions are replaced with noops. We simulate that + * by creating a fake jump as the only new instruction. + * + * 3. In some cases, the alternative section includes an instruction which + * conditionally jumps to the _end_ of the entry. We have to modify these + * jumps' destinations to point back to .text rather than the end of the + * entry in .altinstr_replacement. + * + * 4. It has been requested that we don't validate the !POPCNT feature path + * which is a "very very small percentage of machines". + */ +static int handle_group_alt(struct objtool_file *file, + struct special_alt *special_alt, + struct instruction *orig_insn, + struct instruction **new_insn) +{ + struct instruction *last_orig_insn, *last_new_insn, *insn, *fake_jump; + unsigned long dest_off; + + last_orig_insn = NULL; + insn = orig_insn; + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != special_alt->orig_sec || + insn->offset >= special_alt->orig_off + special_alt->orig_len) + break; + + if (special_alt->skip_orig) + insn->type = INSN_NOP; + + insn->alt_group = true; + last_orig_insn = insn; + } + + if (list_is_last(&last_orig_insn->list, &file->insns) || + list_next_entry(last_orig_insn, list)->sec != special_alt->orig_sec) { + WARN("%s: don't know how to handle alternatives at end of section", + special_alt->orig_sec->name); + return -1; + } + + fake_jump = malloc(sizeof(*fake_jump)); + if (!fake_jump) { + WARN("malloc failed"); + return -1; + } + memset(fake_jump, 0, sizeof(*fake_jump)); + INIT_LIST_HEAD(&fake_jump->alts); + fake_jump->sec = special_alt->new_sec; + fake_jump->offset = -1; + fake_jump->type = INSN_JUMP_UNCONDITIONAL; + fake_jump->jump_dest = list_next_entry(last_orig_insn, list); + + if (!special_alt->new_len) { + *new_insn = fake_jump; + return 0; + } + + last_new_insn = NULL; + insn = *new_insn; + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != special_alt->new_sec || + insn->offset >= special_alt->new_off + special_alt->new_len) + break; + + last_new_insn = insn; + + if (insn->type != INSN_JUMP_CONDITIONAL && + insn->type != INSN_JUMP_UNCONDITIONAL) + continue; + + if (!insn->immediate) + continue; + + dest_off = insn->offset + insn->len + insn->immediate; + if (dest_off == special_alt->new_off + special_alt->new_len) + insn->jump_dest = fake_jump; + + if (!insn->jump_dest) { + WARN_FUNC("can't find alternative jump destination", + insn->sec, insn->offset); + return -1; + } + } + + if (!last_new_insn) { + WARN_FUNC("can't find last new alternative instruction", + special_alt->new_sec, special_alt->new_off); + return -1; + } + + list_add(&fake_jump->list, &last_new_insn->list); + + return 0; +} + +/* + * A jump table entry can either convert a nop to a jump or a jump to a nop. + * If the original instruction is a jump, make the alt entry an effective nop + * by just skipping the original instruction. + */ +static int handle_jump_alt(struct objtool_file *file, + struct special_alt *special_alt, + struct instruction *orig_insn, + struct instruction **new_insn) +{ + if (orig_insn->type == INSN_NOP) + return 0; + + if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) { + WARN_FUNC("unsupported instruction at jump label", + orig_insn->sec, orig_insn->offset); + return -1; + } + + *new_insn = list_next_entry(orig_insn, list); + return 0; +} + +/* + * Read all the special sections which have alternate instructions which can be + * patched in or redirected to at runtime. Each instruction having alternate + * instruction(s) has them added to its insn->alts list, which will be + * traversed in validate_branch(). + */ +static int get_special_section_alts(struct objtool_file *file) +{ + struct list_head special_alts; + struct instruction *orig_insn, *new_insn; + struct special_alt *special_alt, *tmp; + struct alternative *alt; + int ret; + + ret = special_get_alts(file->elf, &special_alts); + if (ret) + return ret; + + list_for_each_entry_safe(special_alt, tmp, &special_alts, list) { + alt = malloc(sizeof(*alt)); + if (!alt) { + WARN("malloc failed"); + ret = -1; + goto out; + } + + orig_insn = find_instruction(file, special_alt->orig_sec, + special_alt->orig_off); + if (!orig_insn) { + WARN_FUNC("special: can't find orig instruction", + special_alt->orig_sec, special_alt->orig_off); + ret = -1; + goto out; + } + + new_insn = NULL; + if (!special_alt->group || special_alt->new_len) { + new_insn = find_instruction(file, special_alt->new_sec, + special_alt->new_off); + if (!new_insn) { + WARN_FUNC("special: can't find new instruction", + special_alt->new_sec, + special_alt->new_off); + ret = -1; + goto out; + } + } + + if (special_alt->group) { + ret = handle_group_alt(file, special_alt, orig_insn, + &new_insn); + if (ret) + goto out; + } else if (special_alt->jump_or_nop) { + ret = handle_jump_alt(file, special_alt, orig_insn, + &new_insn); + if (ret) + goto out; + } + + alt->insn = new_insn; + list_add_tail(&alt->list, &orig_insn->alts); + + list_del(&special_alt->list); + free(special_alt); + } + +out: + return ret; +} + +/* + * For some switch statements, gcc generates a jump table in the .rodata + * section which contains a list of addresses within the function to jump to. + * This finds these jump tables and adds them to the insn->alts lists. + */ +static int get_switch_alts(struct objtool_file *file) +{ + struct instruction *insn, *alt_insn; + struct rela *rodata_rela, *rela; + struct section *rodata; + struct symbol *func; + struct alternative *alt; + + list_for_each_entry(insn, &file->insns, list) { + if (insn->type != INSN_JUMP_DYNAMIC) + continue; + + rodata_rela = find_rela_by_dest_range(insn->sec, insn->offset, + insn->len); + if (!rodata_rela || strcmp(rodata_rela->sym->name, ".rodata")) + continue; + + rodata = find_section_by_name(file->elf, ".rodata"); + if (!rodata || !rodata->rela) + continue; + + /* common case: jmpq *[addr](,%rax,8) */ + rela = find_rela_by_dest(rodata, rodata_rela->addend); + + /* rare case: jmpq *[addr](%rip) */ + if (!rela) + rela = find_rela_by_dest(rodata, + rodata_rela->addend + 4); + if (!rela) + continue; + + func = find_containing_func(insn->sec, insn->offset); + if (!func) { + WARN_FUNC("can't find containing func", + insn->sec, insn->offset); + return -1; + } + + list_for_each_entry_from(rela, &rodata->rela->relas, list) { + if (rela->sym->sec != insn->sec || + rela->addend <= func->offset || + rela->addend >= func->offset + func->len) + break; + + alt_insn = find_instruction(file, insn->sec, + rela->addend); + if (!alt_insn) { + WARN("%s: can't find instruction at %s+0x%x", + rodata->rela->name, insn->sec->name, + rela->addend); + return -1; + } + + alt = malloc(sizeof(*alt)); + if (!alt) { + WARN("malloc failed"); + return -1; + } + + alt->insn = alt_insn; + list_add_tail(&alt->list, &insn->alts); + } + } + + return 0; +} + +static int decode_sections(struct objtool_file *file) +{ + int ret; + + ret = decode_instructions(file); + if (ret) + return ret; + + get_ignores(file); + + ret = get_jump_destinations(file); + if (ret) + return ret; + + ret = get_call_destinations(file); + if (ret) + return ret; + + ret = get_special_section_alts(file); + if (ret) + return ret; + + ret = get_switch_alts(file); + if (ret) + return ret; + + return 0; +} + +static bool is_fentry_call(struct instruction *insn) +{ + if (insn->type == INSN_CALL && + insn->call_dest->type == STT_NOTYPE && + !strcmp(insn->call_dest->name, "__fentry__")) + return true; + + return false; +} + +static bool has_modified_stack_frame(struct instruction *insn) +{ + return (insn->state & STATE_FP_SAVED) || + (insn->state & STATE_FP_SETUP); +} + +static bool has_valid_stack_frame(struct instruction *insn) +{ + return (insn->state & STATE_FP_SAVED) && + (insn->state & STATE_FP_SETUP); +} + +/* + * Follow the branch starting at the given instruction, and recursively follow + * any other branches (jumps). Meanwhile, track the frame pointer state at + * each instruction and validate all the rules described in + * tools/objtool/Documentation/stack-validation.txt. + */ +static int validate_branch(struct objtool_file *file, + struct instruction *first, unsigned char first_state) +{ + struct alternative *alt; + struct instruction *insn; + struct section *sec; + unsigned char state; + int ret, warnings = 0; + + insn = first; + sec = insn->sec; + state = first_state; + + if (insn->alt_group && list_empty(&insn->alts)) { + WARN_FUNC("don't know how to handle branch to middle of alternative instruction group", + sec, insn->offset); + warnings++; + } + + while (1) { + if (insn->visited) { + if (insn->state != state) { + WARN_FUNC("frame pointer state mismatch", + sec, insn->offset); + warnings++; + } + + return warnings; + } + + /* + * Catch a rare case where a noreturn function falls through to + * the next function. + */ + if (is_fentry_call(insn) && (state & STATE_FENTRY)) + return warnings; + + insn->visited = true; + insn->state = state; + + list_for_each_entry(alt, &insn->alts, list) { + ret = validate_branch(file, alt->insn, state); + warnings += ret; + } + + switch (insn->type) { + + case INSN_FP_SAVE: + if (!nofp) { + if (state & STATE_FP_SAVED) { + WARN_FUNC("duplicate frame pointer save", + sec, insn->offset); + warnings++; + } + state |= STATE_FP_SAVED; + } + break; + + case INSN_FP_SETUP: + if (!nofp) { + if (state & STATE_FP_SETUP) { + WARN_FUNC("duplicate frame pointer setup", + sec, insn->offset); + warnings++; + } + state |= STATE_FP_SETUP; + } + break; + + case INSN_FP_RESTORE: + if (!nofp) { + if (has_valid_stack_frame(insn)) + state &= ~STATE_FP_SETUP; + + state &= ~STATE_FP_SAVED; + } + break; + + case INSN_RETURN: + if (!nofp && has_modified_stack_frame(insn)) { + WARN_FUNC("return without frame pointer restore", + sec, insn->offset); + warnings++; + } + return warnings; + + case INSN_CALL: + if (is_fentry_call(insn)) { + state |= STATE_FENTRY; + break; + } + + if (dead_end_function(file, insn->call_dest)) + return warnings; + + /* fallthrough */ + case INSN_CALL_DYNAMIC: + if (!nofp && !has_valid_stack_frame(insn)) { + WARN_FUNC("call without frame pointer save/setup", + sec, insn->offset); + warnings++; + } + break; + + case INSN_JUMP_CONDITIONAL: + case INSN_JUMP_UNCONDITIONAL: + if (insn->jump_dest) { + ret = validate_branch(file, insn->jump_dest, + state); + warnings += ret; + } else if (has_modified_stack_frame(insn)) { + WARN_FUNC("sibling call from callable instruction with changed frame pointer", + sec, insn->offset); + warnings++; + } /* else it's a sibling call */ + + if (insn->type == INSN_JUMP_UNCONDITIONAL) + return warnings; + + break; + + case INSN_JUMP_DYNAMIC: + if (list_empty(&insn->alts) && + has_modified_stack_frame(insn)) { + WARN_FUNC("sibling call from callable instruction with changed frame pointer", + sec, insn->offset); + warnings++; + } + + return warnings; + + case INSN_BUG: + return warnings; + + default: + break; + } + + insn = list_next_entry(insn, list); + + if (&insn->list == &file->insns || insn->sec != sec) { + WARN("%s: unexpected end of section", sec->name); + warnings++; + return warnings; + } + } + + return warnings; +} + +static bool is_gcov_insn(struct instruction *insn) +{ + struct rela *rela; + struct section *sec; + struct symbol *sym; + unsigned long offset; + + rela = find_rela_by_dest_range(insn->sec, insn->offset, insn->len); + if (!rela) + return false; + + if (rela->sym->type != STT_SECTION) + return false; + + sec = rela->sym->sec; + offset = rela->addend + insn->offset + insn->len - rela->offset; + + list_for_each_entry(sym, &sec->symbols, list) { + if (sym->type != STT_OBJECT) + continue; + + if (offset >= sym->offset && offset < sym->offset + sym->len) + return (!memcmp(sym->name, "__gcov0.", 8)); + } + + return false; +} + +static bool is_kasan_insn(struct instruction *insn) +{ + return (insn->type == INSN_CALL && + !strcmp(insn->call_dest->name, "__asan_handle_no_return")); +} + +static bool is_ubsan_insn(struct instruction *insn) +{ + return (insn->type == INSN_CALL && + !strcmp(insn->call_dest->name, + "__ubsan_handle_builtin_unreachable")); +} + +static bool ignore_unreachable_insn(struct instruction *insn, + unsigned long func_end) +{ + int i; + + if (insn->type == INSN_NOP) + return true; + + if (is_gcov_insn(insn)) + return true; + + /* + * Check if this (or a subsequent) instruction is related to + * CONFIG_UBSAN or CONFIG_KASAN. + * + * End the search at 5 instructions to avoid going into the weeds. + */ + for (i = 0; i < 5; i++) { + + if (is_kasan_insn(insn) || is_ubsan_insn(insn)) + return true; + + if (insn->type == INSN_JUMP_UNCONDITIONAL && insn->jump_dest) { + insn = insn->jump_dest; + continue; + } + + if (insn->offset + insn->len >= func_end) + break; + insn = list_next_entry(insn, list); + } + + return false; +} + +static int validate_functions(struct objtool_file *file) +{ + struct section *sec; + struct symbol *func; + struct instruction *insn; + unsigned long func_end; + int ret, warnings = 0; + + list_for_each_entry(sec, &file->elf->sections, list) { + list_for_each_entry(func, &sec->symbols, list) { + if (func->type != STT_FUNC) + continue; + + insn = find_instruction(file, sec, func->offset); + if (!insn) { + WARN("%s(): can't find starting instruction", + func->name); + warnings++; + continue; + } + + ret = validate_branch(file, insn, 0); + warnings += ret; + } + } + + list_for_each_entry(sec, &file->elf->sections, list) { + list_for_each_entry(func, &sec->symbols, list) { + if (func->type != STT_FUNC) + continue; + + insn = find_instruction(file, sec, func->offset); + if (!insn) + continue; + + func_end = func->offset + func->len; + + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func_end) + break; + + if (insn->visited) + continue; + + if (!ignore_unreachable_insn(insn, func_end)) { + WARN_FUNC("function has unreachable instruction", insn->sec, insn->offset); + warnings++; + } + + insn->visited = true; + } + } + } + + return warnings; +} + +static int validate_uncallable_instructions(struct objtool_file *file) +{ + struct instruction *insn; + int warnings = 0; + + list_for_each_entry(insn, &file->insns, list) { + if (!insn->visited && insn->type == INSN_RETURN) { + WARN_FUNC("return instruction outside of a callable function", + insn->sec, insn->offset); + warnings++; + } + } + + return warnings; +} + +static void cleanup(struct objtool_file *file) +{ + struct instruction *insn, *tmpinsn; + struct alternative *alt, *tmpalt; + + list_for_each_entry_safe(insn, tmpinsn, &file->insns, list) { + list_for_each_entry_safe(alt, tmpalt, &insn->alts, list) { + list_del(&alt->list); + free(alt); + } + list_del(&insn->list); + free(insn); + } + elf_close(file->elf); +} + +const char * const check_usage[] = { + "objtool check [] file.o", + NULL, +}; + +int cmd_check(int argc, const char **argv) +{ + struct objtool_file file; + int ret, warnings = 0; + + const struct option options[] = { + OPT_BOOLEAN('f', "no-fp", &nofp, "Skip frame pointer validation"), + OPT_END(), + }; + + argc = parse_options(argc, argv, options, check_usage, 0); + + if (argc != 1) + usage_with_options(check_usage, options); + + objname = argv[0]; + + file.elf = elf_open(objname); + if (!file.elf) { + fprintf(stderr, "error reading elf file %s\n", objname); + return 1; + } + + INIT_LIST_HEAD(&file.insns); + + ret = decode_sections(&file); + if (ret < 0) + goto out; + warnings += ret; + + ret = validate_functions(&file); + if (ret < 0) + goto out; + warnings += ret; + + ret = validate_uncallable_instructions(&file); + if (ret < 0) + goto out; + warnings += ret; + +out: + cleanup(&file); + + /* ignore warnings for now until we get all the code cleaned up */ + if (ret || warnings) + return 0; + return 0; +} diff --git a/tools/objtool/builtin.h b/tools/objtool/builtin.h new file mode 100644 index 000000000000..34d2ba78a616 --- /dev/null +++ b/tools/objtool/builtin.h @@ -0,0 +1,22 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ +#ifndef _BUILTIN_H +#define _BUILTIN_H + +extern int cmd_check(int argc, const char **argv); + +#endif /* _BUILTIN_H */ diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c new file mode 100644 index 000000000000..d547e3f6e0ee --- /dev/null +++ b/tools/objtool/elf.c @@ -0,0 +1,403 @@ +/* + * elf.c - ELF access library + * + * Adapted from kpatch (https://github.com/dynup/kpatch): + * Copyright (C) 2013-2015 Josh Poimboeuf + * Copyright (C) 2014 Seth Jennings + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#include +#include +#include +#include +#include +#include +#include + +#include "elf.h" +#include "warn.h" + +struct section *find_section_by_name(struct elf *elf, const char *name) +{ + struct section *sec; + + list_for_each_entry(sec, &elf->sections, list) + if (!strcmp(sec->name, name)) + return sec; + + return NULL; +} + +static struct section *find_section_by_index(struct elf *elf, + unsigned int idx) +{ + struct section *sec; + + list_for_each_entry(sec, &elf->sections, list) + if (sec->idx == idx) + return sec; + + return NULL; +} + +static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx) +{ + struct section *sec; + struct symbol *sym; + + list_for_each_entry(sec, &elf->sections, list) + list_for_each_entry(sym, &sec->symbols, list) + if (sym->idx == idx) + return sym; + + return NULL; +} + +struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset) +{ + struct symbol *sym; + + list_for_each_entry(sym, &sec->symbols, list) + if (sym->type != STT_SECTION && + sym->offset == offset) + return sym; + + return NULL; +} + +struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset, + unsigned int len) +{ + struct rela *rela; + + if (!sec->rela) + return NULL; + + list_for_each_entry(rela, &sec->rela->relas, list) + if (rela->offset >= offset && rela->offset < offset + len) + return rela; + + return NULL; +} + +struct rela *find_rela_by_dest(struct section *sec, unsigned long offset) +{ + return find_rela_by_dest_range(sec, offset, 1); +} + +struct symbol *find_containing_func(struct section *sec, unsigned long offset) +{ + struct symbol *func; + + list_for_each_entry(func, &sec->symbols, list) + if (func->type == STT_FUNC && offset >= func->offset && + offset < func->offset + func->len) + return func; + + return NULL; +} + +static int read_sections(struct elf *elf) +{ + Elf_Scn *s = NULL; + struct section *sec; + size_t shstrndx, sections_nr; + int i; + + if (elf_getshdrnum(elf->elf, §ions_nr)) { + perror("elf_getshdrnum"); + return -1; + } + + if (elf_getshdrstrndx(elf->elf, &shstrndx)) { + perror("elf_getshdrstrndx"); + return -1; + } + + for (i = 0; i < sections_nr; i++) { + sec = malloc(sizeof(*sec)); + if (!sec) { + perror("malloc"); + return -1; + } + memset(sec, 0, sizeof(*sec)); + + INIT_LIST_HEAD(&sec->symbols); + INIT_LIST_HEAD(&sec->relas); + + list_add_tail(&sec->list, &elf->sections); + + s = elf_getscn(elf->elf, i); + if (!s) { + perror("elf_getscn"); + return -1; + } + + sec->idx = elf_ndxscn(s); + + if (!gelf_getshdr(s, &sec->sh)) { + perror("gelf_getshdr"); + return -1; + } + + sec->name = elf_strptr(elf->elf, shstrndx, sec->sh.sh_name); + if (!sec->name) { + perror("elf_strptr"); + return -1; + } + + sec->elf_data = elf_getdata(s, NULL); + if (!sec->elf_data) { + perror("elf_getdata"); + return -1; + } + + if (sec->elf_data->d_off != 0 || + sec->elf_data->d_size != sec->sh.sh_size) { + WARN("unexpected data attributes for %s", sec->name); + return -1; + } + + sec->data = (unsigned long)sec->elf_data->d_buf; + sec->len = sec->elf_data->d_size; + } + + /* sanity check, one more call to elf_nextscn() should return NULL */ + if (elf_nextscn(elf->elf, s)) { + WARN("section entry mismatch"); + return -1; + } + + return 0; +} + +static int read_symbols(struct elf *elf) +{ + struct section *symtab; + struct symbol *sym; + struct list_head *entry, *tmp; + int symbols_nr, i; + + symtab = find_section_by_name(elf, ".symtab"); + if (!symtab) { + WARN("missing symbol table"); + return -1; + } + + symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize; + + for (i = 0; i < symbols_nr; i++) { + sym = malloc(sizeof(*sym)); + if (!sym) { + perror("malloc"); + return -1; + } + memset(sym, 0, sizeof(*sym)); + + sym->idx = i; + + if (!gelf_getsym(symtab->elf_data, i, &sym->sym)) { + perror("gelf_getsym"); + goto err; + } + + sym->name = elf_strptr(elf->elf, symtab->sh.sh_link, + sym->sym.st_name); + if (!sym->name) { + perror("elf_strptr"); + goto err; + } + + sym->type = GELF_ST_TYPE(sym->sym.st_info); + sym->bind = GELF_ST_BIND(sym->sym.st_info); + + if (sym->sym.st_shndx > SHN_UNDEF && + sym->sym.st_shndx < SHN_LORESERVE) { + sym->sec = find_section_by_index(elf, + sym->sym.st_shndx); + if (!sym->sec) { + WARN("couldn't find section for symbol %s", + sym->name); + goto err; + } + if (sym->type == STT_SECTION) { + sym->name = sym->sec->name; + sym->sec->sym = sym; + } + } else + sym->sec = find_section_by_index(elf, 0); + + sym->offset = sym->sym.st_value; + sym->len = sym->sym.st_size; + + /* sorted insert into a per-section list */ + entry = &sym->sec->symbols; + list_for_each_prev(tmp, &sym->sec->symbols) { + struct symbol *s; + + s = list_entry(tmp, struct symbol, list); + + if (sym->offset > s->offset) { + entry = tmp; + break; + } + + if (sym->offset == s->offset && sym->len >= s->len) { + entry = tmp; + break; + } + } + list_add(&sym->list, entry); + } + + return 0; + +err: + free(sym); + return -1; +} + +static int read_relas(struct elf *elf) +{ + struct section *sec; + struct rela *rela; + int i; + unsigned int symndx; + + list_for_each_entry(sec, &elf->sections, list) { + if (sec->sh.sh_type != SHT_RELA) + continue; + + sec->base = find_section_by_name(elf, sec->name + 5); + if (!sec->base) { + WARN("can't find base section for rela section %s", + sec->name); + return -1; + } + + sec->base->rela = sec; + + for (i = 0; i < sec->sh.sh_size / sec->sh.sh_entsize; i++) { + rela = malloc(sizeof(*rela)); + if (!rela) { + perror("malloc"); + return -1; + } + memset(rela, 0, sizeof(*rela)); + + list_add_tail(&rela->list, &sec->relas); + + if (!gelf_getrela(sec->elf_data, i, &rela->rela)) { + perror("gelf_getrela"); + return -1; + } + + rela->type = GELF_R_TYPE(rela->rela.r_info); + rela->addend = rela->rela.r_addend; + rela->offset = rela->rela.r_offset; + symndx = GELF_R_SYM(rela->rela.r_info); + rela->sym = find_symbol_by_index(elf, symndx); + if (!rela->sym) { + WARN("can't find rela entry symbol %d for %s", + symndx, sec->name); + return -1; + } + } + } + + return 0; +} + +struct elf *elf_open(const char *name) +{ + struct elf *elf; + + elf_version(EV_CURRENT); + + elf = malloc(sizeof(*elf)); + if (!elf) { + perror("malloc"); + return NULL; + } + memset(elf, 0, sizeof(*elf)); + + INIT_LIST_HEAD(&elf->sections); + + elf->name = strdup(name); + if (!elf->name) { + perror("strdup"); + goto err; + } + + elf->fd = open(name, O_RDONLY); + if (elf->fd == -1) { + perror("open"); + goto err; + } + + elf->elf = elf_begin(elf->fd, ELF_C_READ_MMAP, NULL); + if (!elf->elf) { + perror("elf_begin"); + goto err; + } + + if (!gelf_getehdr(elf->elf, &elf->ehdr)) { + perror("gelf_getehdr"); + goto err; + } + + if (read_sections(elf)) + goto err; + + if (read_symbols(elf)) + goto err; + + if (read_relas(elf)) + goto err; + + return elf; + +err: + elf_close(elf); + return NULL; +} + +void elf_close(struct elf *elf) +{ + struct section *sec, *tmpsec; + struct symbol *sym, *tmpsym; + struct rela *rela, *tmprela; + + list_for_each_entry_safe(sec, tmpsec, &elf->sections, list) { + list_for_each_entry_safe(sym, tmpsym, &sec->symbols, list) { + list_del(&sym->list); + free(sym); + } + list_for_each_entry_safe(rela, tmprela, &sec->relas, list) { + list_del(&rela->list); + free(rela); + } + list_del(&sec->list); + free(sec); + } + if (elf->name) + free(elf->name); + if (elf->fd > 0) + close(elf->fd); + if (elf->elf) + elf_end(elf->elf); + free(elf); +} diff --git a/tools/objtool/elf.h b/tools/objtool/elf.h new file mode 100644 index 000000000000..66919de57e68 --- /dev/null +++ b/tools/objtool/elf.h @@ -0,0 +1,79 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#ifndef _OBJTOOL_ELF_H +#define _OBJTOOL_ELF_H + +#include +#include +#include + +struct section { + struct list_head list; + GElf_Shdr sh; + struct list_head symbols; + struct list_head relas; + struct section *base, *rela; + struct symbol *sym; + Elf_Data *elf_data; + char *name; + int idx; + unsigned long data; + unsigned int len; +}; + +struct symbol { + struct list_head list; + GElf_Sym sym; + struct section *sec; + char *name; + int idx; + unsigned char bind, type; + unsigned long offset; + unsigned int len; +}; + +struct rela { + struct list_head list; + GElf_Rela rela; + struct symbol *sym; + unsigned int type; + int offset; + int addend; +}; + +struct elf { + Elf *elf; + GElf_Ehdr ehdr; + int fd; + char *name; + struct list_head sections; +}; + + +struct elf *elf_open(const char *name); +struct section *find_section_by_name(struct elf *elf, const char *name); +struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset); +struct rela *find_rela_by_dest(struct section *sec, unsigned long offset); +struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset, + unsigned int len); +struct symbol *find_containing_func(struct section *sec, unsigned long offset); +void elf_close(struct elf *elf); + + + +#endif /* _OBJTOOL_ELF_H */ diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c new file mode 100644 index 000000000000..46c326db4f46 --- /dev/null +++ b/tools/objtool/objtool.c @@ -0,0 +1,136 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +/* + * objtool: + * + * The 'check' subcmd analyzes every .o file and ensures the validity of its + * stack trace metadata. It enforces a set of rules on asm code and C inline + * assembly code so that stack traces can be reliable. + * + * For more information, see tools/objtool/Documentation/stack-validation.txt. + */ + +#include +#include +#include +#include +#include +#include + +#include "builtin.h" + +#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0])) + +struct cmd_struct { + const char *name; + int (*fn)(int, const char **); + const char *help; +}; + +static const char objtool_usage_string[] = + "objtool [OPTIONS] COMMAND [ARGS]"; + +static struct cmd_struct objtool_cmds[] = { + {"check", cmd_check, "Perform stack metadata validation on an object file" }, +}; + +bool help; + +static void cmd_usage(void) +{ + unsigned int i, longest = 0; + + printf("\n usage: %s\n\n", objtool_usage_string); + + for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) { + if (longest < strlen(objtool_cmds[i].name)) + longest = strlen(objtool_cmds[i].name); + } + + puts(" Commands:"); + for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) { + printf(" %-*s ", longest, objtool_cmds[i].name); + puts(objtool_cmds[i].help); + } + + printf("\n"); + + exit(1); +} + +static void handle_options(int *argc, const char ***argv) +{ + while (*argc > 0) { + const char *cmd = (*argv)[0]; + + if (cmd[0] != '-') + break; + + if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h")) { + help = true; + break; + } else { + fprintf(stderr, "Unknown option: %s\n", cmd); + fprintf(stderr, "\n Usage: %s\n", + objtool_usage_string); + exit(1); + } + + (*argv)++; + (*argc)--; + } +} + +static void handle_internal_command(int argc, const char **argv) +{ + const char *cmd = argv[0]; + unsigned int i, ret; + + for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) { + struct cmd_struct *p = objtool_cmds+i; + + if (strcmp(p->name, cmd)) + continue; + + ret = p->fn(argc, argv); + + exit(ret); + } + + cmd_usage(); +} + +int main(int argc, const char **argv) +{ + static const char *UNUSED = "OBJTOOL_NOT_IMPLEMENTED"; + + /* libsubcmd init */ + exec_cmd_init("objtool", UNUSED, UNUSED, UNUSED); + pager_init(UNUSED); + + argv++; + argc--; + handle_options(&argc, &argv); + + if (!argc || help) + cmd_usage(); + + handle_internal_command(argc, argv); + + return 0; +} diff --git a/tools/objtool/special.c b/tools/objtool/special.c new file mode 100644 index 000000000000..bff8abb3a4aa --- /dev/null +++ b/tools/objtool/special.c @@ -0,0 +1,193 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +/* + * This file reads all the special sections which have alternate instructions + * which can be patched in or redirected to at runtime. + */ + +#include +#include + +#include "special.h" +#include "warn.h" + +#define EX_ENTRY_SIZE 12 +#define EX_ORIG_OFFSET 0 +#define EX_NEW_OFFSET 4 + +#define JUMP_ENTRY_SIZE 24 +#define JUMP_ORIG_OFFSET 0 +#define JUMP_NEW_OFFSET 8 + +#define ALT_ENTRY_SIZE 13 +#define ALT_ORIG_OFFSET 0 +#define ALT_NEW_OFFSET 4 +#define ALT_FEATURE_OFFSET 8 +#define ALT_ORIG_LEN_OFFSET 10 +#define ALT_NEW_LEN_OFFSET 11 + +#define X86_FEATURE_POPCNT (4*32+23) + +struct special_entry { + const char *sec; + bool group, jump_or_nop; + unsigned char size, orig, new; + unsigned char orig_len, new_len; /* group only */ + unsigned char feature; /* ALTERNATIVE macro CPU feature */ +}; + +struct special_entry entries[] = { + { + .sec = ".altinstructions", + .group = true, + .size = ALT_ENTRY_SIZE, + .orig = ALT_ORIG_OFFSET, + .orig_len = ALT_ORIG_LEN_OFFSET, + .new = ALT_NEW_OFFSET, + .new_len = ALT_NEW_LEN_OFFSET, + .feature = ALT_FEATURE_OFFSET, + }, + { + .sec = "__jump_table", + .jump_or_nop = true, + .size = JUMP_ENTRY_SIZE, + .orig = JUMP_ORIG_OFFSET, + .new = JUMP_NEW_OFFSET, + }, + { + .sec = "__ex_table", + .size = EX_ENTRY_SIZE, + .orig = EX_ORIG_OFFSET, + .new = EX_NEW_OFFSET, + }, + {}, +}; + +static int get_alt_entry(struct elf *elf, struct special_entry *entry, + struct section *sec, int idx, + struct special_alt *alt) +{ + struct rela *orig_rela, *new_rela; + unsigned long offset; + + offset = idx * entry->size; + + alt->group = entry->group; + alt->jump_or_nop = entry->jump_or_nop; + + if (alt->group) { + alt->orig_len = *(unsigned char *)(sec->data + offset + + entry->orig_len); + alt->new_len = *(unsigned char *)(sec->data + offset + + entry->new_len); + } + + if (entry->feature) { + unsigned short feature; + + feature = *(unsigned short *)(sec->data + offset + + entry->feature); + + /* + * It has been requested that we don't validate the !POPCNT + * feature path which is a "very very small percentage of + * machines". + */ + if (feature == X86_FEATURE_POPCNT) + alt->skip_orig = true; + } + + orig_rela = find_rela_by_dest(sec, offset + entry->orig); + if (!orig_rela) { + WARN_FUNC("can't find orig rela", sec, offset + entry->orig); + return -1; + } + if (orig_rela->sym->type != STT_SECTION) { + WARN_FUNC("don't know how to handle non-section rela symbol %s", + sec, offset + entry->orig, orig_rela->sym->name); + return -1; + } + + alt->orig_sec = orig_rela->sym->sec; + alt->orig_off = orig_rela->addend; + + if (!entry->group || alt->new_len) { + new_rela = find_rela_by_dest(sec, offset + entry->new); + if (!new_rela) { + WARN_FUNC("can't find new rela", + sec, offset + entry->new); + return -1; + } + + alt->new_sec = new_rela->sym->sec; + alt->new_off = (unsigned int)new_rela->addend; + + /* _ASM_EXTABLE_EX hack */ + if (alt->new_off >= 0x7ffffff0) + alt->new_off -= 0x7ffffff0; + } + + return 0; +} + +/* + * Read all the special sections and create a list of special_alt structs which + * describe all the alternate instructions which can be patched in or + * redirected to at runtime. + */ +int special_get_alts(struct elf *elf, struct list_head *alts) +{ + struct special_entry *entry; + struct section *sec; + unsigned int nr_entries; + struct special_alt *alt; + int idx, ret; + + INIT_LIST_HEAD(alts); + + for (entry = entries; entry->sec; entry++) { + sec = find_section_by_name(elf, entry->sec); + if (!sec) + continue; + + if (sec->len % entry->size != 0) { + WARN("%s size not a multiple of %d", + sec->name, entry->size); + return -1; + } + + nr_entries = sec->len / entry->size; + + for (idx = 0; idx < nr_entries; idx++) { + alt = malloc(sizeof(*alt)); + if (!alt) { + WARN("malloc failed"); + return -1; + } + memset(alt, 0, sizeof(*alt)); + + ret = get_alt_entry(elf, entry, sec, idx, alt); + if (ret) + return ret; + + list_add_tail(&alt->list, alts); + } + } + + return 0; +} diff --git a/tools/objtool/special.h b/tools/objtool/special.h new file mode 100644 index 000000000000..fad1d092f679 --- /dev/null +++ b/tools/objtool/special.h @@ -0,0 +1,42 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#ifndef _SPECIAL_H +#define _SPECIAL_H + +#include +#include "elf.h" + +struct special_alt { + struct list_head list; + + bool group; + bool skip_orig; + bool jump_or_nop; + + struct section *orig_sec; + unsigned long orig_off; + + struct section *new_sec; + unsigned long new_off; + + unsigned int orig_len, new_len; /* group only */ +}; + +int special_get_alts(struct elf *elf, struct list_head *alts); + +#endif /* _SPECIAL_H */ diff --git a/tools/objtool/warn.h b/tools/objtool/warn.h new file mode 100644 index 000000000000..ac7e07523e84 --- /dev/null +++ b/tools/objtool/warn.h @@ -0,0 +1,60 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#ifndef _WARN_H +#define _WARN_H + +extern const char *objname; + +static inline char *offstr(struct section *sec, unsigned long offset) +{ + struct symbol *func; + char *name, *str; + unsigned long name_off; + + func = find_containing_func(sec, offset); + if (func) { + name = func->name; + name_off = offset - func->offset; + } else { + name = sec->name; + name_off = offset; + } + + str = malloc(strlen(name) + 20); + + if (func) + sprintf(str, "%s()+0x%lx", name, name_off); + else + sprintf(str, "%s+0x%lx", name, name_off); + + return str; +} + +#define WARN(format, ...) \ + fprintf(stderr, \ + "%s: warning: objtool: " format "\n", \ + objname, ##__VA_ARGS__) + +#define WARN_FUNC(format, sec, offset, ...) \ +({ \ + char *_str = offstr(sec, offset); \ + WARN("%s: " format, _str, ##__VA_ARGS__); \ + free(_str); \ +}) + +#endif /* _WARN_H */ From b9ab5ebb14ec389bd80f66613f1fe3f8f65f2521 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:42 -0600 Subject: [PATCH 36/52] objtool: Add CONFIG_STACK_VALIDATION option Add a CONFIG_STACK_VALIDATION option which will run "objtool check" for each .o file to ensure the validity of its stack metadata. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/92baab69a6bf9bc7043af0bfca9fb964a1d45546.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- Makefile | 5 ++++- arch/Kconfig | 6 ++++++ lib/Kconfig.debug | 12 ++++++++++++ scripts/Makefile.build | 39 +++++++++++++++++++++++++++++++++++---- 4 files changed, 57 insertions(+), 5 deletions(-) diff --git a/Makefile b/Makefile index fbe1b921798f..62be03b2add4 100644 --- a/Makefile +++ b/Makefile @@ -993,7 +993,10 @@ prepare0: archprepare FORCE $(Q)$(MAKE) $(build)=. # All the preparing.. -prepare: prepare0 +prepare: prepare0 prepare-objtool + +PHONY += prepare-objtool +prepare-objtool: $(if $(CONFIG_STACK_VALIDATION), tools/objtool FORCE) # Generate some files # --------------------------------------------------------------------------- diff --git a/arch/Kconfig b/arch/Kconfig index f6b649d88ec8..81869a5e7e17 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -583,6 +583,12 @@ config HAVE_COPY_THREAD_TLS normal C parameter passing, rather than extracting the syscall argument from pt_regs. +config HAVE_STACK_VALIDATION + bool + help + Architecture supports the 'objtool check' host tool command, which + performs compile-time stack metadata validation. + # # ABI hall of shame # diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 8bfd1aca7a3d..855265621863 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -342,6 +342,18 @@ config FRAME_POINTER larger and slower, but it gives very useful debugging information in case of kernel bugs. (precise oopses/stacktraces/warnings) +config STACK_VALIDATION + bool "Compile-time stack metadata validation" + depends on HAVE_STACK_VALIDATION + default n + help + Add compile-time checks to validate stack metadata, including frame + pointers (if CONFIG_FRAME_POINTER is enabled). This helps ensure + that runtime stack traces are more reliable. + + For more information, see + tools/objtool/Documentation/stack-validation.txt. + config DEBUG_FORCE_WEAK_PER_CPU bool "Force weak per-cpu definitions" depends on DEBUG_KERNEL diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 2c47f9c305aa..130a452d42ee 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -241,10 +241,32 @@ cmd_record_mcount = \ fi; endif +ifdef CONFIG_STACK_VALIDATION + +__objtool_obj := $(objtree)/tools/objtool/objtool + +objtool_args = check +ifndef CONFIG_FRAME_POINTER +objtool_args += --no-fp +endif + +# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory +# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file +# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file +cmd_objtool = $(if $(patsubst y%,, \ + $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \ + $(__objtool_obj) $(objtool_args) "$(@)";) +objtool_obj = $(if $(patsubst y%,, \ + $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \ + $(__objtool_obj)) + +endif # CONFIG_STACK_VALIDATION + define rule_cc_o_c $(call echo-cmd,checksrc) $(cmd_checksrc) \ $(call echo-cmd,cc_o_c) $(cmd_cc_o_c); \ $(cmd_modversions) \ + $(cmd_objtool) \ $(call echo-cmd,record_mcount) \ $(cmd_record_mcount) \ scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' > \ @@ -253,14 +275,23 @@ define rule_cc_o_c mv -f $(dot-target).tmp $(dot-target).cmd endef +define rule_as_o_S + $(call echo-cmd,as_o_S) $(cmd_as_o_S); \ + $(cmd_objtool) \ + scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,as_o_S)' > \ + $(dot-target).tmp; \ + rm -f $(depfile); \ + mv -f $(dot-target).tmp $(dot-target).cmd +endef + # Built-in and composite module parts -$(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE +$(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE $(call cmd,force_checksrc) $(call if_changed_rule,cc_o_c) # Single-part modules are special since we need to mark them in $(MODVERDIR) -$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE +$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE $(call cmd,force_checksrc) $(call if_changed_rule,cc_o_c) @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod) @@ -290,8 +321,8 @@ $(obj)/%.s: $(src)/%.S FORCE quiet_cmd_as_o_S = AS $(quiet_modtag) $@ cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< -$(obj)/%.o: $(src)/%.S FORCE - $(call if_changed_dep,as_o_S) +$(obj)/%.o: $(src)/%.S $(objtool_obj) FORCE + $(call if_changed_rule,as_o_S) targets += $(real-objs-y) $(real-objs-m) $(lib-y) targets += $(extra-y) $(MAKECMDGOALS) $(always) From d4883d5d6b146fd65f762c462b2c6d4a327c7d50 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Sun, 28 Feb 2016 22:22:43 -0600 Subject: [PATCH 37/52] objtool: Enable stack metadata validation on 64-bit x86 Set HAVE_STACK_VALIDATION to enable stack metadata validation for x86_64. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/cdaeb6914d00a070c0f455cd06989bf3f787a2f6.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index c46662f64c39..adc5a6d28735 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -155,6 +155,7 @@ config X86 select VIRT_TO_BUS select X86_DEV_DMA_OPS if X86_64 select X86_FEATURE_NAMES if PROC_FS + select HAVE_STACK_VALIDATION if X86_64 config INSTRUCTION_DECODER def_bool y From 19072f23d1d785c093b7f81cb1fb161e7a13ecc0 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 2 Mar 2016 18:39:36 -0600 Subject: [PATCH 38/52] x86/asm/decoder: Use explicitly signed chars When running objtool on a ppc64le host to analyze x86 binaries, it reports a lot of false warnings like: ipc/compat_mq.o: warning: objtool: compat_SyS_mq_open()+0x91: can't find jump dest instruction at .text+0x3a5 The warnings are caused by the x86 instruction decoder setting the wrong value for the jump instruction's immediate field because it assumes that "char == signed char", which isn't true for all architectures. When converting char to int, gcc sign-extends on x86 but doesn't sign-extend on ppc64le. According to the gcc man page, that's a feature, not a bug: > Each kind of machine has a default for what "char" should be. It is > either like "unsigned char" by default or like "signed char" by > default. > > Ideally, a portable program should always use "signed char" or > "unsigned char" when it depends on the signedness of an object. Conform to the "standards" by changing the "char" casts to "signed char". This results in no actual changes to the object code on x86. Note: the x86 decoder now lives in three different locations in the kernel tree, which are all kept in sync via makefile checks and warnings: in-kernel, perf, and objtool. This fixes all three locations. Eventually we should probably try to at least converge the two separate "tools" locations into a single shared location. Signed-off-by: Josh Poimboeuf Cc: Adrian Hunter Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Michael Ellerman Cc: Peter Zijlstra Cc: Stephen Rothwell Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/9dd4161719b20e6def9564646d68bfbe498c549f.1456962210.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/lib/insn.c | 6 +++--- tools/objtool/arch/x86/insn/insn.c | 6 +++--- tools/perf/util/intel-pt-decoder/insn.c | 6 +++--- 3 files changed, 9 insertions(+), 9 deletions(-) diff --git a/arch/x86/lib/insn.c b/arch/x86/lib/insn.c index 8f72b334aea0..1a416935bac9 100644 --- a/arch/x86/lib/insn.c +++ b/arch/x86/lib/insn.c @@ -374,7 +374,7 @@ void insn_get_displacement(struct insn *insn) if (mod == 3) goto out; if (mod == 1) { - insn->displacement.value = get_next(char, insn); + insn->displacement.value = get_next(signed char, insn); insn->displacement.nbytes = 1; } else if (insn->addr_bytes == 2) { if ((mod == 0 && rm == 6) || mod == 2) { @@ -532,7 +532,7 @@ void insn_get_immediate(struct insn *insn) switch (inat_immediate_size(insn->attr)) { case INAT_IMM_BYTE: - insn->immediate.value = get_next(char, insn); + insn->immediate.value = get_next(signed char, insn); insn->immediate.nbytes = 1; break; case INAT_IMM_WORD: @@ -566,7 +566,7 @@ void insn_get_immediate(struct insn *insn) goto err_out; } if (inat_has_second_immediate(insn->attr)) { - insn->immediate2.value = get_next(char, insn); + insn->immediate2.value = get_next(signed char, insn); insn->immediate2.nbytes = 1; } done: diff --git a/tools/objtool/arch/x86/insn/insn.c b/tools/objtool/arch/x86/insn/insn.c index 47314a64399c..9f26eae6c9f0 100644 --- a/tools/objtool/arch/x86/insn/insn.c +++ b/tools/objtool/arch/x86/insn/insn.c @@ -374,7 +374,7 @@ void insn_get_displacement(struct insn *insn) if (mod == 3) goto out; if (mod == 1) { - insn->displacement.value = get_next(char, insn); + insn->displacement.value = get_next(signed char, insn); insn->displacement.nbytes = 1; } else if (insn->addr_bytes == 2) { if ((mod == 0 && rm == 6) || mod == 2) { @@ -532,7 +532,7 @@ void insn_get_immediate(struct insn *insn) switch (inat_immediate_size(insn->attr)) { case INAT_IMM_BYTE: - insn->immediate.value = get_next(char, insn); + insn->immediate.value = get_next(signed char, insn); insn->immediate.nbytes = 1; break; case INAT_IMM_WORD: @@ -566,7 +566,7 @@ void insn_get_immediate(struct insn *insn) goto err_out; } if (inat_has_second_immediate(insn->attr)) { - insn->immediate2.value = get_next(char, insn); + insn->immediate2.value = get_next(signed char, insn); insn->immediate2.nbytes = 1; } done: diff --git a/tools/perf/util/intel-pt-decoder/insn.c b/tools/perf/util/intel-pt-decoder/insn.c index 47314a64399c..9f26eae6c9f0 100644 --- a/tools/perf/util/intel-pt-decoder/insn.c +++ b/tools/perf/util/intel-pt-decoder/insn.c @@ -374,7 +374,7 @@ void insn_get_displacement(struct insn *insn) if (mod == 3) goto out; if (mod == 1) { - insn->displacement.value = get_next(char, insn); + insn->displacement.value = get_next(signed char, insn); insn->displacement.nbytes = 1; } else if (insn->addr_bytes == 2) { if ((mod == 0 && rm == 6) || mod == 2) { @@ -532,7 +532,7 @@ void insn_get_immediate(struct insn *insn) switch (inat_immediate_size(insn->attr)) { case INAT_IMM_BYTE: - insn->immediate.value = get_next(char, insn); + insn->immediate.value = get_next(signed char, insn); insn->immediate.nbytes = 1; break; case INAT_IMM_WORD: @@ -566,7 +566,7 @@ void insn_get_immediate(struct insn *insn) goto err_out; } if (inat_has_second_immediate(insn->attr)) { - insn->immediate2.value = get_next(char, insn); + insn->immediate2.value = get_next(signed char, insn); insn->immediate2.nbytes = 1; } done: From c1d45c3abd49b5bf9447e435099c1b000dcde752 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 2 Mar 2016 18:39:37 -0600 Subject: [PATCH 39/52] objtool: Support CROSS_COMPILE When building with CONFIG_STACK_VALIDATION on a ppc64le host with an x86 cross-compiler, Stephen Rothwell saw the following objtool build errors: DESCEND objtool CC /home/sfr/next/x86_64_allmodconfig/tools/objtool/builtin-check.o CC /home/sfr/next/x86_64_allmodconfig/tools/objtool/special.o CC /home/sfr/next/x86_64_allmodconfig/tools/objtool/elf.o CC /home/sfr/next/x86_64_allmodconfig/tools/objtool/objtool.o MKDIR /home/sfr/next/x86_64_allmodconfig/tools/objtool/arch/x86/insn/ CC /home/sfr/next/x86_64_allmodconfig/tools/objtool/libstring.o elf.c:22:23: fatal error: sys/types.h: No such file or directory compilation terminated. CC /home/sfr/next/x86_64_allmodconfig/tools/objtool/exec-cmd.o CC /home/sfr/next/x86_64_allmodconfig/tools/objtool/help.o builtin-check.c:28:20: fatal error: string.h: No such file or directory compilation terminated. objtool.c:28:19: fatal error: stdio.h: No such file or directory compilation terminated. It fails to build because it tries to compile objtool with the cross-compiler instead of the host compiler. Ensure that it always uses the host compiler by ignoring CROSS_COMPILE. In order to do that properly, the libsubcmd.a library needs to be built in tools/objtool/ rather than tools/lib/subcmd/. The latter directory contains the cross-compiled version which is needed for perf and possibly other tools. Note that cross-compiling for x86 on a _big_ endian system would result in a bunch of false positive objtool warnings during the kernel build because it isn't endian-aware. But that's generally a rare edge case and there haven't been any reports of anybody needing that. Reported-by: Stephen Rothwell Signed-off-by: Josh Poimboeuf Cc: Adrian Hunter Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Michael Ellerman Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/55b63eefc347f1bb28573f972d8d1adbf1f1c31d.1456962210.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/lib/subcmd/Makefile | 6 ++++-- tools/objtool/Makefile | 17 ++++++++++------- 2 files changed, 14 insertions(+), 9 deletions(-) diff --git a/tools/lib/subcmd/Makefile b/tools/lib/subcmd/Makefile index 629cf8c14e68..1faecb82ad42 100644 --- a/tools/lib/subcmd/Makefile +++ b/tools/lib/subcmd/Makefile @@ -8,8 +8,10 @@ srctree := $(patsubst %/,%,$(dir $(srctree))) #$(info Determined 'srctree' to be $(srctree)) endif -CC = $(CROSS_COMPILE)gcc -AR = $(CROSS_COMPILE)ar +CC ?= $(CROSS_COMPILE)gcc +LD ?= $(CROSS_COMPILE)ld +AR ?= $(CROSS_COMPILE)ar + RM = rm -f MAKEFLAGS += --no-print-directory diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile index c4f0713a1eb7..e4a6bd528bf0 100644 --- a/tools/objtool/Makefile +++ b/tools/objtool/Makefile @@ -7,13 +7,19 @@ ARCH := x86 endif endif +# always use the host compiler +CC = gcc +LD = ld +AR = ar + ifeq ($(srctree),) srctree := $(patsubst %/,%,$(dir $(shell pwd))) srctree := $(patsubst %/,%,$(dir $(srctree))) endif -SUBCMD_SRCDIR = $(srctree)/tools/lib/subcmd/ -LIBSUBCMD = $(if $(OUTPUT),$(OUTPUT),$(SUBCMD_SRCDIR))libsubcmd.a +SUBCMD_SRCDIR = $(srctree)/tools/lib/subcmd/ +LIBSUBCMD_OUTPUT = $(if $(OUTPUT),$(OUTPUT),$(PWD)/) +LIBSUBCMD = $(LIBSUBCMD_OUTPUT)libsubcmd.a OBJTOOL := $(OUTPUT)objtool OBJTOOL_IN := $(OBJTOOL)-in.o @@ -45,12 +51,9 @@ $(OBJTOOL): $(LIBSUBCMD) $(OBJTOOL_IN) $(LIBSUBCMD): fixdep FORCE - $(Q)$(MAKE) -C $(SUBCMD_SRCDIR) + $(Q)$(MAKE) -C $(SUBCMD_SRCDIR) OUTPUT=$(LIBSUBCMD_OUTPUT) -$(LIBSUBCMD)-clean: - $(Q)$(MAKE) -C $(SUBCMD_SRCDIR) clean > /dev/null - -clean: $(LIBSUBCMD)-clean +clean: $(call QUIET_CLEAN, objtool) $(RM) $(OBJTOOL) $(Q)find $(OUTPUT) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete $(Q)$(RM) $(OUTPUT)arch/x86/insn/inat-tables.c $(OUTPUT)fixdep From e17cf3a80d4ba0c4e40bf1a89deb1354c2e10e14 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 3 Mar 2016 08:53:43 -0600 Subject: [PATCH 40/52] tools: Support relative directory path for 'O=' Running "make O=foo" (with a relative directory path) fails with: scripts/Makefile.include:3: *** O=foo does not exist. Stop. /home/jpoimboe/git/linux/Makefile:1547: recipe for target 'tools/objtool' failed The tools Makefile gets confused by the relative path and tries to build objtool in tools/foo. Convert the output directory to an absolute path before passing it to the tools Makefile. Reported-by: Sudip Mukherjee Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephen Rothwell Cc: Thomas Gleixner Cc: linux-next@vger.kernel.org Cc: linux@roeck-us.net Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/94a078c6c998fac9f01a14f574008bf7dff40191.1457016803.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index 62be03b2add4..2c27a01c42f1 100644 --- a/Makefile +++ b/Makefile @@ -1509,11 +1509,11 @@ image_name: # Clear a bunch of variables before executing the submake tools/: FORCE $(Q)mkdir -p $(objtree)/tools - $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(O) subdir=tools -C $(src)/tools/ + $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ tools/%: FORCE $(Q)mkdir -p $(objtree)/tools - $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(O) subdir=tools -C $(src)/tools/ $* + $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $* # Single targets # --------------------------------------------------------------------------- From 3b27a0c85d7068130ed8e3977a2e977ade986841 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 3 Mar 2016 11:39:30 -0600 Subject: [PATCH 41/52] objtool: Detect and warn if libelf is missing and don't break the build With CONFIG_STACK_VALIDATION enabled, if the host system doesn't have a development version of libelf installed, the build fails with errors like: elf.h:22:18: fatal error: gelf.h: No such file or directory compilation terminated. Instead of failing to build, instead just print a warning and disable stack validation. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephen Rothwell Cc: Sudip Mukherjee Cc: Thomas Gleixner Cc: linux-next@vger.kernel.org Cc: linux@roeck-us.net Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/8c27fe00face60f42e888ddb3142c97e45223165.1457026550.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- Makefile | 13 ++++++++++++- scripts/Makefile.build | 2 ++ 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 2c27a01c42f1..60b729540785 100644 --- a/Makefile +++ b/Makefile @@ -995,8 +995,19 @@ prepare0: archprepare FORCE # All the preparing.. prepare: prepare0 prepare-objtool +ifdef CONFIG_STACK_VALIDATION + has_libelf := $(shell echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf - &> /dev/null && echo 1 || echo 0) + ifeq ($(has_libelf),1) + objtool_target := tools/objtool FORCE + else + $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev or elfutils-libelf-devel") + SKIP_STACK_VALIDATION := 1 + export SKIP_STACK_VALIDATION + endif +endif + PHONY += prepare-objtool -prepare-objtool: $(if $(CONFIG_STACK_VALIDATION), tools/objtool FORCE) +prepare-objtool: $(objtool_target) # Generate some files # --------------------------------------------------------------------------- diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 130a452d42ee..e1bc1907090e 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -242,6 +242,7 @@ cmd_record_mcount = \ endif ifdef CONFIG_STACK_VALIDATION +ifneq ($(SKIP_STACK_VALIDATION),1) __objtool_obj := $(objtree)/tools/objtool/objtool @@ -260,6 +261,7 @@ objtool_obj = $(if $(patsubst y%,, \ $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \ $(__objtool_obj)) +endif # SKIP_STACK_VALIDATION endif # CONFIG_STACK_VALIDATION define rule_cc_o_c From 81bfafca1332869160e9da789252276e2f34a14e Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:51 -0600 Subject: [PATCH 42/52] objtool: Prevent infinite recursion in noreturn detection Ingo reported an infinite loop in objtool with a certain randconfig [1]. With the given config, two functions in crypto/ablkcipher.o contained sibling calls to each other, which threw the recursive call in dead_end_function() for a loop (literally!). Split the noreturn detection into two passes. In the first pass, check for return instructions. In the second pass, do the potentially recursive sibling call check. In most cases, the first pass will be good enough. In the rare case where a second pass is needed, recursion should hopefully no longer be possible. [1] https://lkml.kernel.org/r/20160308154909.GA20956@gmail.com Reported-by: Ingo Molnar Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/16afb602640ef43b7782087d6cca17bf6fc13603.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index f7e0ebac3fbe..80d9ed90d641 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -125,7 +125,7 @@ static bool ignore_func(struct objtool_file *file, struct symbol *func) static bool dead_end_function(struct objtool_file *file, struct symbol *func) { int i; - struct instruction *insn; + struct instruction *insn, *func_insn; bool empty = true; /* @@ -154,10 +154,11 @@ static bool dead_end_function(struct objtool_file *file, struct symbol *func) if (!func->sec) return false; - insn = find_instruction(file, func->sec, func->offset); - if (!insn) + func_insn = find_instruction(file, func->sec, func->offset); + if (!func_insn) return false; + insn = func_insn; list_for_each_entry_from(insn, &file->insns, list) { if (insn->sec != func->sec || insn->offset >= func->offset + func->len) @@ -167,6 +168,21 @@ static bool dead_end_function(struct objtool_file *file, struct symbol *func) if (insn->type == INSN_RETURN) return false; + } + + if (empty) + return false; + + /* + * A function can have a sibling call instead of a return. In that + * case, the function's dead-end status depends on whether the target + * of the sibling call returns. + */ + insn = func_insn; + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func->offset + func->len) + break; if (insn->type == INSN_JUMP_UNCONDITIONAL) { struct instruction *dest = insn->jump_dest; @@ -194,7 +210,7 @@ static bool dead_end_function(struct objtool_file *file, struct symbol *func) return false; } - return !empty; + return true; } /* From b1e03249510b32645826bbf61a1452dd766c2e5c Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:52 -0600 Subject: [PATCH 43/52] objtool: Detect infinite recursion I don't _think_ dead_end_function() can get into a recursive loop, but just in case, stop the loop and print a warning. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/ff489a63e6feb88abb192cfb361d81626dcf3e89.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 45 +++++++++++++++++++++++++---------- 1 file changed, 33 insertions(+), 12 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index 80d9ed90d641..51da270758f0 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -121,8 +121,14 @@ static bool ignore_func(struct objtool_file *file, struct symbol *func) * * For local functions, we have to detect them manually by simply looking for * the lack of a return instruction. + * + * Returns: + * -1: error + * 0: no dead end + * 1: dead end */ -static bool dead_end_function(struct objtool_file *file, struct symbol *func) +static int __dead_end_function(struct objtool_file *file, struct symbol *func, + int recursion) { int i; struct instruction *insn, *func_insn; @@ -144,19 +150,19 @@ static bool dead_end_function(struct objtool_file *file, struct symbol *func) }; if (func->bind == STB_WEAK) - return false; + return 0; if (func->bind == STB_GLOBAL) for (i = 0; i < ARRAY_SIZE(global_noreturns); i++) if (!strcmp(func->name, global_noreturns[i])) - return true; + return 1; if (!func->sec) - return false; + return 0; func_insn = find_instruction(file, func->sec, func->offset); if (!func_insn) - return false; + return 0; insn = func_insn; list_for_each_entry_from(insn, &file->insns, list) { @@ -167,11 +173,11 @@ static bool dead_end_function(struct objtool_file *file, struct symbol *func) empty = false; if (insn->type == INSN_RETURN) - return false; + return 0; } if (empty) - return false; + return 0; /* * A function can have a sibling call instead of a return. In that @@ -190,7 +196,7 @@ static bool dead_end_function(struct objtool_file *file, struct symbol *func) if (!dest) /* sibling call to another file */ - return false; + return 0; if (dest->sec != func->sec || dest->offset < func->offset || @@ -201,16 +207,28 @@ static bool dead_end_function(struct objtool_file *file, struct symbol *func) if (!dest_func) continue; - return dead_end_function(file, dest_func); + if (recursion == 5) { + WARN_FUNC("infinite recursion (objtool bug!)", + dest->sec, dest->offset); + return -1; + } + + return __dead_end_function(file, dest_func, + recursion + 1); } } if (insn->type == INSN_JUMP_DYNAMIC) /* sibling call */ - return false; + return 0; } - return true; + return 1; +} + +static int dead_end_function(struct objtool_file *file, struct symbol *func) +{ + return __dead_end_function(file, func, 0); } /* @@ -809,8 +827,11 @@ static int validate_branch(struct objtool_file *file, break; } - if (dead_end_function(file, insn->call_dest)) + ret = dead_end_function(file, insn->call_dest); + if (ret == 1) return warnings; + if (ret == -1) + warnings++; /* fallthrough */ case INSN_CALL_DYNAMIC: From d435fb5ef74c31909ca58f93aa87ad09b17bbe9a Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:53 -0600 Subject: [PATCH 44/52] objtool: Compile with debugging symbols Compile objtool with debugging symbols ('-g') to help tools like perf and gdb understand what it's doing. Combined with '-O2', it's not always helpful, but it's better than nothing. Reported-by: Ingo Molnar Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/c295e9ee9ed360dc8b2e1d180c859f11cfc151ef.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile index e4a6bd528bf0..6765c7e949f3 100644 --- a/tools/objtool/Makefile +++ b/tools/objtool/Makefile @@ -27,7 +27,7 @@ OBJTOOL_IN := $(OBJTOOL)-in.o all: $(OBJTOOL) INCLUDES := -I$(srctree)/tools/include -CFLAGS += -Wall -Werror $(EXTRA_WARNINGS) -fomit-frame-pointer -O2 $(INCLUDES) +CFLAGS += -Wall -Werror $(EXTRA_WARNINGS) -fomit-frame-pointer -O2 -g $(INCLUDES) LDFLAGS += -lelf $(LIBSUBCMD) AWK = awk From d8d1b2cb58540b0cf572be4715167c473193888e Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:54 -0600 Subject: [PATCH 45/52] objtool: Fix false positive warnings related to sibling calls With some configs [1], objtool prints a bunch of false positive warnings like: arch/x86/events/core.o: warning: objtool: x86_del_exclusive()+0x0: frame pointer state mismatch For some reason this config has a bunch of sibling calls. When objtool follows a sibling call jump, it attempts to compare the frame pointer state. But it also accidentally compares the FENTRY state, resulting in a false positive warning. [1] https://lkml.kernel.org/r/20160308154909.GA20956@gmail.com Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/382de77ccaaa8cd79b27a155c3d109ebd4ce0219.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index 51da270758f0..fe248044415b 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -729,6 +729,11 @@ static bool has_valid_stack_frame(struct instruction *insn) (insn->state & STATE_FP_SETUP); } +static unsigned int frame_state(unsigned long state) +{ + return (state & (STATE_FP_SAVED | STATE_FP_SETUP)); +} + /* * Follow the branch starting at the given instruction, and recursively follow * any other branches (jumps). Meanwhile, track the frame pointer state at @@ -756,7 +761,7 @@ static int validate_branch(struct objtool_file *file, while (1) { if (insn->visited) { - if (insn->state != state) { + if (frame_state(insn->state) != frame_state(state)) { WARN_FUNC("frame pointer state mismatch", sec, insn->offset); warnings++; From 74aec058beb0bdaf64454291ef4ba176932bfad3 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:55 -0600 Subject: [PATCH 46/52] objtool: Add helper macros for traversing instructions Add some helper macros to make it easier to traverse instructions, and to abstract the details of the instruction list implementation in preparation for creating a hash structure. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/8e1715d5035bc02b4db28d0fccef6bb1170d1f12.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 128 +++++++++++++++------------------- 1 file changed, 55 insertions(+), 73 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index fe248044415b..46a898595390 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -66,9 +66,8 @@ struct objtool_file { const char *objname; static bool nofp; -static struct instruction *find_instruction(struct objtool_file *file, - struct section *sec, - unsigned long offset) +static struct instruction *find_insn(struct objtool_file *file, + struct section *sec, unsigned long offset) { struct instruction *insn; @@ -79,6 +78,31 @@ static struct instruction *find_instruction(struct objtool_file *file, return NULL; } +static struct instruction *next_insn_same_sec(struct objtool_file *file, + struct instruction *insn) +{ + struct instruction *next = list_next_entry(insn, list); + + if (&next->list == &file->insns || next->sec != insn->sec) + return NULL; + + return next; +} + +#define for_each_insn(file, insn) \ + list_for_each_entry(insn, &file->insns, list) + +#define func_for_each_insn(file, func, insn) \ + for (insn = find_insn(file, func->sec, func->offset); \ + insn && &insn->list != &file->insns && \ + insn->sec == func->sec && \ + insn->offset < func->offset + func->len; \ + insn = list_next_entry(insn, list)) + +#define sec_for_each_insn_from(file, insn) \ + for (; insn; insn = next_insn_same_sec(file, insn)) + + /* * Check if the function has been manually whitelisted with the * STACK_FRAME_NON_STANDARD macro, or if it should be automatically whitelisted @@ -99,16 +123,9 @@ static bool ignore_func(struct objtool_file *file, struct symbol *func) return true; /* check if it has a context switching instruction */ - insn = find_instruction(file, func->sec, func->offset); - if (!insn) - return false; - list_for_each_entry_from(insn, &file->insns, list) { - if (insn->sec != func->sec || - insn->offset >= func->offset + func->len) - break; + func_for_each_insn(file, func, insn) if (insn->type == INSN_CONTEXT_SWITCH) return true; - } return false; } @@ -131,7 +148,7 @@ static int __dead_end_function(struct objtool_file *file, struct symbol *func, int recursion) { int i; - struct instruction *insn, *func_insn; + struct instruction *insn; bool empty = true; /* @@ -160,16 +177,7 @@ static int __dead_end_function(struct objtool_file *file, struct symbol *func, if (!func->sec) return 0; - func_insn = find_instruction(file, func->sec, func->offset); - if (!func_insn) - return 0; - - insn = func_insn; - list_for_each_entry_from(insn, &file->insns, list) { - if (insn->sec != func->sec || - insn->offset >= func->offset + func->len) - break; - + func_for_each_insn(file, func, insn) { empty = false; if (insn->type == INSN_RETURN) @@ -184,8 +192,7 @@ static int __dead_end_function(struct objtool_file *file, struct symbol *func, * case, the function's dead-end status depends on whether the target * of the sibling call returns. */ - insn = func_insn; - list_for_each_entry_from(insn, &file->insns, list) { + func_for_each_insn(file, func, insn) { if (insn->sec != func->sec || insn->offset >= func->offset + func->len) break; @@ -294,17 +301,8 @@ static void get_ignores(struct objtool_file *file) if (!ignore_func(file, func)) continue; - insn = find_instruction(file, sec, func->offset); - if (!insn) - continue; - - list_for_each_entry_from(insn, &file->insns, list) { - if (insn->sec != func->sec || - insn->offset >= func->offset + func->len) - break; - + func_for_each_insn(file, func, insn) insn->visited = true; - } } } } @@ -319,7 +317,7 @@ static int get_jump_destinations(struct objtool_file *file) struct section *dest_sec; unsigned long dest_off; - list_for_each_entry(insn, &file->insns, list) { + for_each_insn(file, insn) { if (insn->type != INSN_JUMP_CONDITIONAL && insn->type != INSN_JUMP_UNCONDITIONAL) continue; @@ -345,7 +343,7 @@ static int get_jump_destinations(struct objtool_file *file) continue; } - insn->jump_dest = find_instruction(file, dest_sec, dest_off); + insn->jump_dest = find_insn(file, dest_sec, dest_off); if (!insn->jump_dest) { /* @@ -375,7 +373,7 @@ static int get_call_destinations(struct objtool_file *file) unsigned long dest_off; struct rela *rela; - list_for_each_entry(insn, &file->insns, list) { + for_each_insn(file, insn) { if (insn->type != INSN_CALL) continue; @@ -438,9 +436,8 @@ static int handle_group_alt(struct objtool_file *file, last_orig_insn = NULL; insn = orig_insn; - list_for_each_entry_from(insn, &file->insns, list) { - if (insn->sec != special_alt->orig_sec || - insn->offset >= special_alt->orig_off + special_alt->orig_len) + sec_for_each_insn_from(file, insn) { + if (insn->offset >= special_alt->orig_off + special_alt->orig_len) break; if (special_alt->skip_orig) @@ -450,8 +447,7 @@ static int handle_group_alt(struct objtool_file *file, last_orig_insn = insn; } - if (list_is_last(&last_orig_insn->list, &file->insns) || - list_next_entry(last_orig_insn, list)->sec != special_alt->orig_sec) { + if (!next_insn_same_sec(file, last_orig_insn)) { WARN("%s: don't know how to handle alternatives at end of section", special_alt->orig_sec->name); return -1; @@ -476,9 +472,8 @@ static int handle_group_alt(struct objtool_file *file, last_new_insn = NULL; insn = *new_insn; - list_for_each_entry_from(insn, &file->insns, list) { - if (insn->sec != special_alt->new_sec || - insn->offset >= special_alt->new_off + special_alt->new_len) + sec_for_each_insn_from(file, insn) { + if (insn->offset >= special_alt->new_off + special_alt->new_len) break; last_new_insn = insn; @@ -561,8 +556,8 @@ static int get_special_section_alts(struct objtool_file *file) goto out; } - orig_insn = find_instruction(file, special_alt->orig_sec, - special_alt->orig_off); + orig_insn = find_insn(file, special_alt->orig_sec, + special_alt->orig_off); if (!orig_insn) { WARN_FUNC("special: can't find orig instruction", special_alt->orig_sec, special_alt->orig_off); @@ -572,8 +567,8 @@ static int get_special_section_alts(struct objtool_file *file) new_insn = NULL; if (!special_alt->group || special_alt->new_len) { - new_insn = find_instruction(file, special_alt->new_sec, - special_alt->new_off); + new_insn = find_insn(file, special_alt->new_sec, + special_alt->new_off); if (!new_insn) { WARN_FUNC("special: can't find new instruction", special_alt->new_sec, @@ -619,7 +614,7 @@ static int get_switch_alts(struct objtool_file *file) struct symbol *func; struct alternative *alt; - list_for_each_entry(insn, &file->insns, list) { + for_each_insn(file, insn) { if (insn->type != INSN_JUMP_DYNAMIC) continue; @@ -655,8 +650,7 @@ static int get_switch_alts(struct objtool_file *file) rela->addend >= func->offset + func->len) break; - alt_insn = find_instruction(file, insn->sec, - rela->addend); + alt_insn = find_insn(file, insn->sec, rela->addend); if (!alt_insn) { WARN("%s: can't find instruction at %s+0x%x", rodata->rela->name, insn->sec->name, @@ -881,9 +875,8 @@ static int validate_branch(struct objtool_file *file, break; } - insn = list_next_entry(insn, list); - - if (&insn->list == &file->insns || insn->sec != sec) { + insn = next_insn_same_sec(file, insn); + if (!insn) { WARN("%s: unexpected end of section", sec->name); warnings++; return warnings; @@ -934,8 +927,8 @@ static bool is_ubsan_insn(struct instruction *insn) "__ubsan_handle_builtin_unreachable")); } -static bool ignore_unreachable_insn(struct instruction *insn, - unsigned long func_end) +static bool ignore_unreachable_insn(struct symbol *func, + struct instruction *insn) { int i; @@ -961,7 +954,7 @@ static bool ignore_unreachable_insn(struct instruction *insn, continue; } - if (insn->offset + insn->len >= func_end) + if (insn->offset + insn->len >= func->offset + func->len) break; insn = list_next_entry(insn, list); } @@ -974,7 +967,6 @@ static int validate_functions(struct objtool_file *file) struct section *sec; struct symbol *func; struct instruction *insn; - unsigned long func_end; int ret, warnings = 0; list_for_each_entry(sec, &file->elf->sections, list) { @@ -982,7 +974,7 @@ static int validate_functions(struct objtool_file *file) if (func->type != STT_FUNC) continue; - insn = find_instruction(file, sec, func->offset); + insn = find_insn(file, sec, func->offset); if (!insn) { WARN("%s(): can't find starting instruction", func->name); @@ -1000,21 +992,11 @@ static int validate_functions(struct objtool_file *file) if (func->type != STT_FUNC) continue; - insn = find_instruction(file, sec, func->offset); - if (!insn) - continue; - - func_end = func->offset + func->len; - - list_for_each_entry_from(insn, &file->insns, list) { - if (insn->sec != func->sec || - insn->offset >= func_end) - break; - + func_for_each_insn(file, func, insn) { if (insn->visited) continue; - if (!ignore_unreachable_insn(insn, func_end)) { + if (!ignore_unreachable_insn(func, insn)) { WARN_FUNC("function has unreachable instruction", insn->sec, insn->offset); warnings++; } @@ -1032,7 +1014,7 @@ static int validate_uncallable_instructions(struct objtool_file *file) struct instruction *insn; int warnings = 0; - list_for_each_entry(insn, &file->insns, list) { + for_each_insn(file, insn) { if (!insn->visited && insn->type == INSN_RETURN) { WARN_FUNC("return instruction outside of a callable function", insn->sec, insn->offset); From e2a5f18a1ba11e8b1e9ee53b6fca4be12bb5749e Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:56 -0600 Subject: [PATCH 47/52] objtool: Remove superflous INIT_LIST_HEAD The insns list is initialized twice, in cmd_check() and in decode_instructions(). Remove the latter. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/be6e21d7eec1f072095d22a1cbe144057135e097.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index 46a898595390..a974f295dc42 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -249,8 +249,6 @@ static int decode_instructions(struct objtool_file *file) struct instruction *insn; int ret; - INIT_LIST_HEAD(&file->insns); - list_for_each_entry(sec, &file->elf->sections, list) { if (!(sec->sh.sh_flags & SHF_EXECINSTR)) From a196e17198224cacd2d992f12cb6d81d354de82f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:57 -0600 Subject: [PATCH 48/52] objtool: Rename some variables and functions Rename some list heads to distinguish them from hash node heads, which are added later in the patch series. Also rename the get_*() functions to add_*(), which is more descriptive: they "add" data to the objtool_file struct. Also rename rodata_rela and text_rela to be clearer: - text_rela refers to a rela entry in .rela.text. - rodata_rela refers to a rela entry in .rela.rodata. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/ee0eca2bba8482aa45758958c5586c00a7b71e62.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 80 ++++++++++++++++++----------------- tools/objtool/elf.c | 22 +++++----- tools/objtool/elf.h | 4 +- 3 files changed, 54 insertions(+), 52 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index a974f295dc42..cdbdd7d9333a 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -60,7 +60,7 @@ struct alternative { struct objtool_file { struct elf *elf; - struct list_head insns; + struct list_head insn_list; }; const char *objname; @@ -71,7 +71,7 @@ static struct instruction *find_insn(struct objtool_file *file, { struct instruction *insn; - list_for_each_entry(insn, &file->insns, list) + list_for_each_entry(insn, &file->insn_list, list) if (insn->sec == sec && insn->offset == offset) return insn; @@ -83,18 +83,18 @@ static struct instruction *next_insn_same_sec(struct objtool_file *file, { struct instruction *next = list_next_entry(insn, list); - if (&next->list == &file->insns || next->sec != insn->sec) + if (&next->list == &file->insn_list || next->sec != insn->sec) return NULL; return next; } #define for_each_insn(file, insn) \ - list_for_each_entry(insn, &file->insns, list) + list_for_each_entry(insn, &file->insn_list, list) #define func_for_each_insn(file, func, insn) \ for (insn = find_insn(file, func->sec, func->offset); \ - insn && &insn->list != &file->insns && \ + insn && &insn->list != &file->insn_list && \ insn->sec == func->sec && \ insn->offset < func->offset + func->len; \ insn = list_next_entry(insn, list)) @@ -117,7 +117,7 @@ static bool ignore_func(struct objtool_file *file, struct symbol *func) /* check for STACK_FRAME_NON_STANDARD */ macro_sec = find_section_by_name(file->elf, "__func_stack_frame_non_standard"); if (macro_sec && macro_sec->rela) - list_for_each_entry(rela, ¯o_sec->rela->relas, list) + list_for_each_entry(rela, ¯o_sec->rela->rela_list, list) if (rela->sym->sec == func->sec && rela->addend == func->offset) return true; @@ -240,7 +240,7 @@ static int dead_end_function(struct objtool_file *file, struct symbol *func) /* * Call the arch-specific instruction decoder for all the instructions and add - * them to the global insns list. + * them to the global instruction list. */ static int decode_instructions(struct objtool_file *file) { @@ -275,7 +275,7 @@ static int decode_instructions(struct objtool_file *file) return -1; } - list_add_tail(&insn->list, &file->insns); + list_add_tail(&insn->list, &file->insn_list); } } @@ -285,14 +285,14 @@ static int decode_instructions(struct objtool_file *file) /* * Warnings shouldn't be reported for ignored functions. */ -static void get_ignores(struct objtool_file *file) +static void add_ignores(struct objtool_file *file) { struct instruction *insn; struct section *sec; struct symbol *func; list_for_each_entry(sec, &file->elf->sections, list) { - list_for_each_entry(func, &sec->symbols, list) { + list_for_each_entry(func, &sec->symbol_list, list) { if (func->type != STT_FUNC) continue; @@ -308,7 +308,7 @@ static void get_ignores(struct objtool_file *file) /* * Find the destination instructions for all jumps. */ -static int get_jump_destinations(struct objtool_file *file) +static int add_jump_destinations(struct objtool_file *file) { struct instruction *insn; struct rela *rela; @@ -365,7 +365,7 @@ static int get_jump_destinations(struct objtool_file *file) /* * Find the destination instructions for all calls. */ -static int get_call_destinations(struct objtool_file *file) +static int add_call_destinations(struct objtool_file *file) { struct instruction *insn; unsigned long dest_off; @@ -534,7 +534,7 @@ static int handle_jump_alt(struct objtool_file *file, * instruction(s) has them added to its insn->alts list, which will be * traversed in validate_branch(). */ -static int get_special_section_alts(struct objtool_file *file) +static int add_special_section_alts(struct objtool_file *file) { struct list_head special_alts; struct instruction *orig_insn, *new_insn; @@ -604,10 +604,10 @@ static int get_special_section_alts(struct objtool_file *file) * section which contains a list of addresses within the function to jump to. * This finds these jump tables and adds them to the insn->alts lists. */ -static int get_switch_alts(struct objtool_file *file) +static int add_switch_table_alts(struct objtool_file *file) { struct instruction *insn, *alt_insn; - struct rela *rodata_rela, *rela; + struct rela *rodata_rela, *text_rela; struct section *rodata; struct symbol *func; struct alternative *alt; @@ -616,9 +616,9 @@ static int get_switch_alts(struct objtool_file *file) if (insn->type != INSN_JUMP_DYNAMIC) continue; - rodata_rela = find_rela_by_dest_range(insn->sec, insn->offset, - insn->len); - if (!rodata_rela || strcmp(rodata_rela->sym->name, ".rodata")) + text_rela = find_rela_by_dest_range(insn->sec, insn->offset, + insn->len); + if (!text_rela || strcmp(text_rela->sym->name, ".rodata")) continue; rodata = find_section_by_name(file->elf, ".rodata"); @@ -626,13 +626,13 @@ static int get_switch_alts(struct objtool_file *file) continue; /* common case: jmpq *[addr](,%rax,8) */ - rela = find_rela_by_dest(rodata, rodata_rela->addend); + rodata_rela = find_rela_by_dest(rodata, text_rela->addend); /* rare case: jmpq *[addr](%rip) */ - if (!rela) - rela = find_rela_by_dest(rodata, - rodata_rela->addend + 4); - if (!rela) + if (!rodata_rela) + rodata_rela = find_rela_by_dest(rodata, + text_rela->addend + 4); + if (!rodata_rela) continue; func = find_containing_func(insn->sec, insn->offset); @@ -642,17 +642,19 @@ static int get_switch_alts(struct objtool_file *file) return -1; } - list_for_each_entry_from(rela, &rodata->rela->relas, list) { - if (rela->sym->sec != insn->sec || - rela->addend <= func->offset || - rela->addend >= func->offset + func->len) + list_for_each_entry_from(rodata_rela, &rodata->rela->rela_list, + list) { + if (rodata_rela->sym->sec != insn->sec || + rodata_rela->addend <= func->offset || + rodata_rela->addend >= func->offset + func->len) break; - alt_insn = find_insn(file, insn->sec, rela->addend); + alt_insn = find_insn(file, insn->sec, + rodata_rela->addend); if (!alt_insn) { WARN("%s: can't find instruction at %s+0x%x", rodata->rela->name, insn->sec->name, - rela->addend); + rodata_rela->addend); return -1; } @@ -678,21 +680,21 @@ static int decode_sections(struct objtool_file *file) if (ret) return ret; - get_ignores(file); + add_ignores(file); - ret = get_jump_destinations(file); + ret = add_jump_destinations(file); if (ret) return ret; - ret = get_call_destinations(file); + ret = add_call_destinations(file); if (ret) return ret; - ret = get_special_section_alts(file); + ret = add_special_section_alts(file); if (ret) return ret; - ret = get_switch_alts(file); + ret = add_switch_table_alts(file); if (ret) return ret; @@ -901,7 +903,7 @@ static bool is_gcov_insn(struct instruction *insn) sec = rela->sym->sec; offset = rela->addend + insn->offset + insn->len - rela->offset; - list_for_each_entry(sym, &sec->symbols, list) { + list_for_each_entry(sym, &sec->symbol_list, list) { if (sym->type != STT_OBJECT) continue; @@ -968,7 +970,7 @@ static int validate_functions(struct objtool_file *file) int ret, warnings = 0; list_for_each_entry(sec, &file->elf->sections, list) { - list_for_each_entry(func, &sec->symbols, list) { + list_for_each_entry(func, &sec->symbol_list, list) { if (func->type != STT_FUNC) continue; @@ -986,7 +988,7 @@ static int validate_functions(struct objtool_file *file) } list_for_each_entry(sec, &file->elf->sections, list) { - list_for_each_entry(func, &sec->symbols, list) { + list_for_each_entry(func, &sec->symbol_list, list) { if (func->type != STT_FUNC) continue; @@ -1028,7 +1030,7 @@ static void cleanup(struct objtool_file *file) struct instruction *insn, *tmpinsn; struct alternative *alt, *tmpalt; - list_for_each_entry_safe(insn, tmpinsn, &file->insns, list) { + list_for_each_entry_safe(insn, tmpinsn, &file->insn_list, list) { list_for_each_entry_safe(alt, tmpalt, &insn->alts, list) { list_del(&alt->list); free(alt); @@ -1067,7 +1069,7 @@ int cmd_check(int argc, const char **argv) return 1; } - INIT_LIST_HEAD(&file.insns); + INIT_LIST_HEAD(&file.insn_list); ret = decode_sections(&file); if (ret < 0) diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index d547e3f6e0ee..7de243f0a7be 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -59,7 +59,7 @@ static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx) struct symbol *sym; list_for_each_entry(sec, &elf->sections, list) - list_for_each_entry(sym, &sec->symbols, list) + list_for_each_entry(sym, &sec->symbol_list, list) if (sym->idx == idx) return sym; @@ -70,7 +70,7 @@ struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset) { struct symbol *sym; - list_for_each_entry(sym, &sec->symbols, list) + list_for_each_entry(sym, &sec->symbol_list, list) if (sym->type != STT_SECTION && sym->offset == offset) return sym; @@ -86,7 +86,7 @@ struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset, if (!sec->rela) return NULL; - list_for_each_entry(rela, &sec->rela->relas, list) + list_for_each_entry(rela, &sec->rela->rela_list, list) if (rela->offset >= offset && rela->offset < offset + len) return rela; @@ -102,7 +102,7 @@ struct symbol *find_containing_func(struct section *sec, unsigned long offset) { struct symbol *func; - list_for_each_entry(func, &sec->symbols, list) + list_for_each_entry(func, &sec->symbol_list, list) if (func->type == STT_FUNC && offset >= func->offset && offset < func->offset + func->len) return func; @@ -135,8 +135,8 @@ static int read_sections(struct elf *elf) } memset(sec, 0, sizeof(*sec)); - INIT_LIST_HEAD(&sec->symbols); - INIT_LIST_HEAD(&sec->relas); + INIT_LIST_HEAD(&sec->symbol_list); + INIT_LIST_HEAD(&sec->rela_list); list_add_tail(&sec->list, &elf->sections); @@ -244,8 +244,8 @@ static int read_symbols(struct elf *elf) sym->len = sym->sym.st_size; /* sorted insert into a per-section list */ - entry = &sym->sec->symbols; - list_for_each_prev(tmp, &sym->sec->symbols) { + entry = &sym->sec->symbol_list; + list_for_each_prev(tmp, &sym->sec->symbol_list) { struct symbol *s; s = list_entry(tmp, struct symbol, list); @@ -298,7 +298,7 @@ static int read_relas(struct elf *elf) } memset(rela, 0, sizeof(*rela)); - list_add_tail(&rela->list, &sec->relas); + list_add_tail(&rela->list, &sec->rela_list); if (!gelf_getrela(sec->elf_data, i, &rela->rela)) { perror("gelf_getrela"); @@ -382,11 +382,11 @@ void elf_close(struct elf *elf) struct rela *rela, *tmprela; list_for_each_entry_safe(sec, tmpsec, &elf->sections, list) { - list_for_each_entry_safe(sym, tmpsym, &sec->symbols, list) { + list_for_each_entry_safe(sym, tmpsym, &sec->symbol_list, list) { list_del(&sym->list); free(sym); } - list_for_each_entry_safe(rela, tmprela, &sec->relas, list) { + list_for_each_entry_safe(rela, tmprela, &sec->rela_list, list) { list_del(&rela->list); free(rela); } diff --git a/tools/objtool/elf.h b/tools/objtool/elf.h index 66919de57e68..57e4653f8383 100644 --- a/tools/objtool/elf.h +++ b/tools/objtool/elf.h @@ -25,8 +25,8 @@ struct section { struct list_head list; GElf_Shdr sh; - struct list_head symbols; - struct list_head relas; + struct list_head symbol_list; + struct list_head rela_list; struct section *base, *rela; struct symbol *sym; Elf_Data *elf_data; From 8133fbb4240ae2918d993defa0f6824864412f56 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:58 -0600 Subject: [PATCH 49/52] objtool: Fix false positive warnings for functions with multiple switch statements Ingo reported [1] some false positive objtool warnings: drivers/net/wireless/realtek/rtlwifi/base.o: warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch drivers/net/wireless/realtek/rtlwifi/base.o: warning: objtool: rtlwifi_rate_mapping()+0x2f3: frame pointer state mismatch ... And so did the 0-day bot [2]: drivers/gpu/drm/radeon/cik.o: warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup drivers/gpu/drm/radeon/cik.o: warning: objtool: cik_tiling_mode_table_init()+0x72b: call without frame pointer save/setup ... Both sets of warnings involve functions which have multiple switch statements. When there's more than one switch statement in a function, objtool interprets all the switch jump tables as a single table. If the targets of one jump table assume a stack frame and the targets of another one don't, it prints false positive warnings. Fix the bug by detecting the size of each switch jump table. For multiple tables, each one ends where the next one begins. [1] https://lkml.kernel.org/r/20160308103716.GA9618@gmail.com [2] https://lists.01.org/pipermail/kbuild-all/2016-March/018124.html Reported-by: Ingo Molnar Reported-by: kbuild test robot Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/2d7eecc6bc52d301f494b80f5fd62c2b6c895658.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 167 ++++++++++++++++++++++------------ 1 file changed, 111 insertions(+), 56 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index cdbdd7d9333a..cf1e48dbfa97 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -61,6 +61,7 @@ struct alternative { struct objtool_file { struct elf *elf; struct list_head insn_list; + struct section *rodata; }; const char *objname; @@ -599,6 +600,103 @@ static int add_special_section_alts(struct objtool_file *file) return ret; } +static int add_switch_table(struct objtool_file *file, struct symbol *func, + struct instruction *insn, struct rela *table, + struct rela *next_table) +{ + struct rela *rela = table; + struct instruction *alt_insn; + struct alternative *alt; + + list_for_each_entry_from(rela, &file->rodata->rela->rela_list, list) { + if (rela == next_table) + break; + + if (rela->sym->sec != insn->sec || + rela->addend <= func->offset || + rela->addend >= func->offset + func->len) + break; + + alt_insn = find_insn(file, insn->sec, rela->addend); + if (!alt_insn) { + WARN("%s: can't find instruction at %s+0x%x", + file->rodata->rela->name, insn->sec->name, + rela->addend); + return -1; + } + + alt = malloc(sizeof(*alt)); + if (!alt) { + WARN("malloc failed"); + return -1; + } + + alt->insn = alt_insn; + list_add_tail(&alt->list, &insn->alts); + } + + return 0; +} + +static int add_func_switch_tables(struct objtool_file *file, + struct symbol *func) +{ + struct instruction *insn, *prev_jump; + struct rela *text_rela, *rodata_rela, *prev_rela; + int ret; + + prev_jump = NULL; + + func_for_each_insn(file, func, insn) { + if (insn->type != INSN_JUMP_DYNAMIC) + continue; + + text_rela = find_rela_by_dest_range(insn->sec, insn->offset, + insn->len); + if (!text_rela || text_rela->sym != file->rodata->sym) + continue; + + /* common case: jmpq *[addr](,%rax,8) */ + rodata_rela = find_rela_by_dest(file->rodata, + text_rela->addend); + + /* + * TODO: Document where this is needed, or get rid of it. + * + * rare case: jmpq *[addr](%rip) + */ + if (!rodata_rela) + rodata_rela = find_rela_by_dest(file->rodata, + text_rela->addend + 4); + + if (!rodata_rela) + continue; + + /* + * We found a switch table, but we don't know yet how big it + * is. Don't add it until we reach the end of the function or + * the beginning of another switch table in the same function. + */ + if (prev_jump) { + ret = add_switch_table(file, func, prev_jump, prev_rela, + rodata_rela); + if (ret) + return ret; + } + + prev_jump = insn; + prev_rela = rodata_rela; + } + + if (prev_jump) { + ret = add_switch_table(file, func, prev_jump, prev_rela, NULL); + if (ret) + return ret; + } + + return 0; +} + /* * For some switch statements, gcc generates a jump table in the .rodata * section which contains a list of addresses within the function to jump to. @@ -606,66 +704,21 @@ static int add_special_section_alts(struct objtool_file *file) */ static int add_switch_table_alts(struct objtool_file *file) { - struct instruction *insn, *alt_insn; - struct rela *rodata_rela, *text_rela; - struct section *rodata; + struct section *sec; struct symbol *func; - struct alternative *alt; + int ret; - for_each_insn(file, insn) { - if (insn->type != INSN_JUMP_DYNAMIC) - continue; + if (!file->rodata || !file->rodata->rela) + return 0; - text_rela = find_rela_by_dest_range(insn->sec, insn->offset, - insn->len); - if (!text_rela || strcmp(text_rela->sym->name, ".rodata")) - continue; + list_for_each_entry(sec, &file->elf->sections, list) { + list_for_each_entry(func, &sec->symbol_list, list) { + if (func->type != STT_FUNC) + continue; - rodata = find_section_by_name(file->elf, ".rodata"); - if (!rodata || !rodata->rela) - continue; - - /* common case: jmpq *[addr](,%rax,8) */ - rodata_rela = find_rela_by_dest(rodata, text_rela->addend); - - /* rare case: jmpq *[addr](%rip) */ - if (!rodata_rela) - rodata_rela = find_rela_by_dest(rodata, - text_rela->addend + 4); - if (!rodata_rela) - continue; - - func = find_containing_func(insn->sec, insn->offset); - if (!func) { - WARN_FUNC("can't find containing func", - insn->sec, insn->offset); - return -1; - } - - list_for_each_entry_from(rodata_rela, &rodata->rela->rela_list, - list) { - if (rodata_rela->sym->sec != insn->sec || - rodata_rela->addend <= func->offset || - rodata_rela->addend >= func->offset + func->len) - break; - - alt_insn = find_insn(file, insn->sec, - rodata_rela->addend); - if (!alt_insn) { - WARN("%s: can't find instruction at %s+0x%x", - rodata->rela->name, insn->sec->name, - rodata_rela->addend); - return -1; - } - - alt = malloc(sizeof(*alt)); - if (!alt) { - WARN("malloc failed"); - return -1; - } - - alt->insn = alt_insn; - list_add_tail(&alt->list, &insn->alts); + ret = add_func_switch_tables(file, func); + if (ret) + return ret; } } @@ -676,6 +729,8 @@ static int decode_sections(struct objtool_file *file) { int ret; + file->rodata = find_section_by_name(file->elf, ".rodata"); + ret = decode_instructions(file); if (ret) return ret; From 1698872b5c772aebc5c43ca445cc0a79f12b9fcc Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:06:59 -0600 Subject: [PATCH 50/52] tools: Copy hashtable.h into tools directory Copy hashtable.h from include/linux/tools.h. It's needed by objtool in the next patch in the series. Add some includes that it needs, and remove references to kernel-specific features like RCU and __read_mostly. Also change some if its dependency headers' includes to use quotes instead of brackets so gcc can find them. Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/be3bef72f6540d8a510515408119d968a0e18179.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/include/asm-generic/bitops/__fls.h | 2 +- tools/include/asm-generic/bitops/fls.h | 2 +- tools/include/asm-generic/bitops/fls64.h | 2 +- tools/include/linux/hashtable.h | 152 +++++++++++++++++++++++ 4 files changed, 155 insertions(+), 3 deletions(-) create mode 100644 tools/include/linux/hashtable.h diff --git a/tools/include/asm-generic/bitops/__fls.h b/tools/include/asm-generic/bitops/__fls.h index 2218b9add4c1..494c9c615d1c 100644 --- a/tools/include/asm-generic/bitops/__fls.h +++ b/tools/include/asm-generic/bitops/__fls.h @@ -1 +1 @@ -#include <../../../../include/asm-generic/bitops/__fls.h> +#include "../../../../include/asm-generic/bitops/__fls.h" diff --git a/tools/include/asm-generic/bitops/fls.h b/tools/include/asm-generic/bitops/fls.h index dbf711a28f71..0e4995fa0248 100644 --- a/tools/include/asm-generic/bitops/fls.h +++ b/tools/include/asm-generic/bitops/fls.h @@ -1 +1 @@ -#include <../../../../include/asm-generic/bitops/fls.h> +#include "../../../../include/asm-generic/bitops/fls.h" diff --git a/tools/include/asm-generic/bitops/fls64.h b/tools/include/asm-generic/bitops/fls64.h index 980b1f63c047..35bee0071e78 100644 --- a/tools/include/asm-generic/bitops/fls64.h +++ b/tools/include/asm-generic/bitops/fls64.h @@ -1 +1 @@ -#include <../../../../include/asm-generic/bitops/fls64.h> +#include "../../../../include/asm-generic/bitops/fls64.h" diff --git a/tools/include/linux/hashtable.h b/tools/include/linux/hashtable.h new file mode 100644 index 000000000000..c65cc0aa2659 --- /dev/null +++ b/tools/include/linux/hashtable.h @@ -0,0 +1,152 @@ +/* + * Statically sized hash table implementation + * (C) 2012 Sasha Levin + */ + +#ifndef _LINUX_HASHTABLE_H +#define _LINUX_HASHTABLE_H + +#include +#include +#include +#include +#include +#include + +#ifndef ARRAY_SIZE +#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) +#endif + +#define DEFINE_HASHTABLE(name, bits) \ + struct hlist_head name[1 << (bits)] = \ + { [0 ... ((1 << (bits)) - 1)] = HLIST_HEAD_INIT } + +#define DECLARE_HASHTABLE(name, bits) \ + struct hlist_head name[1 << (bits)] + +#define HASH_SIZE(name) (ARRAY_SIZE(name)) +#define HASH_BITS(name) ilog2(HASH_SIZE(name)) + +/* Use hash_32 when possible to allow for fast 32bit hashing in 64bit kernels. */ +#define hash_min(val, bits) \ + (sizeof(val) <= 4 ? hash_32(val, bits) : hash_long(val, bits)) + +static inline void __hash_init(struct hlist_head *ht, unsigned int sz) +{ + unsigned int i; + + for (i = 0; i < sz; i++) + INIT_HLIST_HEAD(&ht[i]); +} + +/** + * hash_init - initialize a hash table + * @hashtable: hashtable to be initialized + * + * Calculates the size of the hashtable from the given parameter, otherwise + * same as hash_init_size. + * + * This has to be a macro since HASH_BITS() will not work on pointers since + * it calculates the size during preprocessing. + */ +#define hash_init(hashtable) __hash_init(hashtable, HASH_SIZE(hashtable)) + +/** + * hash_add - add an object to a hashtable + * @hashtable: hashtable to add to + * @node: the &struct hlist_node of the object to be added + * @key: the key of the object to be added + */ +#define hash_add(hashtable, node, key) \ + hlist_add_head(node, &hashtable[hash_min(key, HASH_BITS(hashtable))]) + +/** + * hash_hashed - check whether an object is in any hashtable + * @node: the &struct hlist_node of the object to be checked + */ +static inline bool hash_hashed(struct hlist_node *node) +{ + return !hlist_unhashed(node); +} + +static inline bool __hash_empty(struct hlist_head *ht, unsigned int sz) +{ + unsigned int i; + + for (i = 0; i < sz; i++) + if (!hlist_empty(&ht[i])) + return false; + + return true; +} + +/** + * hash_empty - check whether a hashtable is empty + * @hashtable: hashtable to check + * + * This has to be a macro since HASH_BITS() will not work on pointers since + * it calculates the size during preprocessing. + */ +#define hash_empty(hashtable) __hash_empty(hashtable, HASH_SIZE(hashtable)) + +/** + * hash_del - remove an object from a hashtable + * @node: &struct hlist_node of the object to remove + */ +static inline void hash_del(struct hlist_node *node) +{ + hlist_del_init(node); +} + +/** + * hash_for_each - iterate over a hashtable + * @name: hashtable to iterate + * @bkt: integer to use as bucket loop cursor + * @obj: the type * to use as a loop cursor for each entry + * @member: the name of the hlist_node within the struct + */ +#define hash_for_each(name, bkt, obj, member) \ + for ((bkt) = 0, obj = NULL; obj == NULL && (bkt) < HASH_SIZE(name);\ + (bkt)++)\ + hlist_for_each_entry(obj, &name[bkt], member) + +/** + * hash_for_each_safe - iterate over a hashtable safe against removal of + * hash entry + * @name: hashtable to iterate + * @bkt: integer to use as bucket loop cursor + * @tmp: a &struct used for temporary storage + * @obj: the type * to use as a loop cursor for each entry + * @member: the name of the hlist_node within the struct + */ +#define hash_for_each_safe(name, bkt, tmp, obj, member) \ + for ((bkt) = 0, obj = NULL; obj == NULL && (bkt) < HASH_SIZE(name);\ + (bkt)++)\ + hlist_for_each_entry_safe(obj, tmp, &name[bkt], member) + +/** + * hash_for_each_possible - iterate over all possible objects hashing to the + * same bucket + * @name: hashtable to iterate + * @obj: the type * to use as a loop cursor for each entry + * @member: the name of the hlist_node within the struct + * @key: the key of the objects to iterate over + */ +#define hash_for_each_possible(name, obj, member, key) \ + hlist_for_each_entry(obj, &name[hash_min(key, HASH_BITS(name))], member) + +/** + * hash_for_each_possible_safe - iterate over all possible objects hashing to the + * same bucket safe against removals + * @name: hashtable to iterate + * @obj: the type * to use as a loop cursor for each entry + * @tmp: a &struct used for temporary storage + * @member: the name of the hlist_node within the struct + * @key: the key of the objects to iterate over + */ +#define hash_for_each_possible_safe(name, obj, tmp, member, key) \ + hlist_for_each_entry_safe(obj, tmp,\ + &name[hash_min(key, HASH_BITS(name))], member) + + +#endif From 042ba73fe7eb63872ee2d6ac86410052210c1f16 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:07:00 -0600 Subject: [PATCH 51/52] objtool: Add several performance improvements Use hash tables for instruction and rela lookups (and keep the linked lists around for sequential access). Also cache the section struct for the "__func_stack_frame_non_standard" section. With this change, "objtool check net/wireless/nl80211.o" goes from: real 0m1.168s user 0m1.163s sys 0m0.005s to: real 0m0.059s user 0m0.042s sys 0m0.017s for a 20x speedup. With the same object, it should be noted that the memory heap usage grew from 8MB to 62MB. Reducing the memory usage is on the TODO list. Reported-by: Ingo Molnar Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/dd0d8e1449506cfa7701b4e7ba73577077c44253.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 18 ++++++++++++------ tools/objtool/elf.c | 21 +++++++++++++++------ tools/objtool/elf.h | 10 ++++++++-- 3 files changed, 35 insertions(+), 14 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index cf1e48dbfa97..bfeee227aaab 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -34,6 +34,8 @@ #include "arch.h" #include "warn.h" +#include + #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) #define STATE_FP_SAVED 0x1 @@ -42,6 +44,7 @@ struct instruction { struct list_head list; + struct hlist_node hash; struct section *sec; unsigned long offset; unsigned int len, state; @@ -61,7 +64,8 @@ struct alternative { struct objtool_file { struct elf *elf; struct list_head insn_list; - struct section *rodata; + DECLARE_HASHTABLE(insn_hash, 16); + struct section *rodata, *whitelist; }; const char *objname; @@ -72,7 +76,7 @@ static struct instruction *find_insn(struct objtool_file *file, { struct instruction *insn; - list_for_each_entry(insn, &file->insn_list, list) + hash_for_each_possible(file->insn_hash, insn, hash, offset) if (insn->sec == sec && insn->offset == offset) return insn; @@ -111,14 +115,12 @@ static struct instruction *next_insn_same_sec(struct objtool_file *file, */ static bool ignore_func(struct objtool_file *file, struct symbol *func) { - struct section *macro_sec; struct rela *rela; struct instruction *insn; /* check for STACK_FRAME_NON_STANDARD */ - macro_sec = find_section_by_name(file->elf, "__func_stack_frame_non_standard"); - if (macro_sec && macro_sec->rela) - list_for_each_entry(rela, ¯o_sec->rela->rela_list, list) + if (file->whitelist && file->whitelist->rela) + list_for_each_entry(rela, &file->whitelist->rela->rela_list, list) if (rela->sym->sec == func->sec && rela->addend == func->offset) return true; @@ -276,6 +278,7 @@ static int decode_instructions(struct objtool_file *file) return -1; } + hash_add(file->insn_hash, &insn->hash, insn->offset); list_add_tail(&insn->list, &file->insn_list); } } @@ -729,6 +732,7 @@ static int decode_sections(struct objtool_file *file) { int ret; + file->whitelist = find_section_by_name(file->elf, "__func_stack_frame_non_standard"); file->rodata = find_section_by_name(file->elf, ".rodata"); ret = decode_instructions(file); @@ -1091,6 +1095,7 @@ static void cleanup(struct objtool_file *file) free(alt); } list_del(&insn->list); + hash_del(&insn->hash); free(insn); } elf_close(file->elf); @@ -1125,6 +1130,7 @@ int cmd_check(int argc, const char **argv) } INIT_LIST_HEAD(&file.insn_list); + hash_init(file.insn_hash); ret = decode_sections(&file); if (ret < 0) diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index 7de243f0a7be..e11f6b69cce6 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -59,7 +59,7 @@ static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx) struct symbol *sym; list_for_each_entry(sec, &elf->sections, list) - list_for_each_entry(sym, &sec->symbol_list, list) + hash_for_each_possible(sec->symbol_hash, sym, hash, idx) if (sym->idx == idx) return sym; @@ -82,13 +82,15 @@ struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset, unsigned int len) { struct rela *rela; + unsigned long o; if (!sec->rela) return NULL; - list_for_each_entry(rela, &sec->rela->rela_list, list) - if (rela->offset >= offset && rela->offset < offset + len) - return rela; + for (o = offset; o < offset + len; o++) + hash_for_each_possible(sec->rela->rela_hash, rela, hash, o) + if (rela->offset == o) + return rela; return NULL; } @@ -137,6 +139,8 @@ static int read_sections(struct elf *elf) INIT_LIST_HEAD(&sec->symbol_list); INIT_LIST_HEAD(&sec->rela_list); + hash_init(sec->rela_hash); + hash_init(sec->symbol_hash); list_add_tail(&sec->list, &elf->sections); @@ -261,6 +265,7 @@ static int read_symbols(struct elf *elf) } } list_add(&sym->list, entry); + hash_add(sym->sec->symbol_hash, &sym->hash, sym->idx); } return 0; @@ -298,8 +303,6 @@ static int read_relas(struct elf *elf) } memset(rela, 0, sizeof(*rela)); - list_add_tail(&rela->list, &sec->rela_list); - if (!gelf_getrela(sec->elf_data, i, &rela->rela)) { perror("gelf_getrela"); return -1; @@ -315,6 +318,10 @@ static int read_relas(struct elf *elf) symndx, sec->name); return -1; } + + list_add_tail(&rela->list, &sec->rela_list); + hash_add(sec->rela_hash, &rela->hash, rela->offset); + } } @@ -384,10 +391,12 @@ void elf_close(struct elf *elf) list_for_each_entry_safe(sec, tmpsec, &elf->sections, list) { list_for_each_entry_safe(sym, tmpsym, &sec->symbol_list, list) { list_del(&sym->list); + hash_del(&sym->hash); free(sym); } list_for_each_entry_safe(rela, tmprela, &sec->rela_list, list) { list_del(&rela->list); + hash_del(&rela->hash); free(rela); } list_del(&sec->list); diff --git a/tools/objtool/elf.h b/tools/objtool/elf.h index 57e4653f8383..7f3e00a2f907 100644 --- a/tools/objtool/elf.h +++ b/tools/objtool/elf.h @@ -21,12 +21,15 @@ #include #include #include +#include struct section { struct list_head list; GElf_Shdr sh; struct list_head symbol_list; + DECLARE_HASHTABLE(symbol_hash, 8); struct list_head rela_list; + DECLARE_HASHTABLE(rela_hash, 16); struct section *base, *rela; struct symbol *sym; Elf_Data *elf_data; @@ -38,10 +41,11 @@ struct section { struct symbol { struct list_head list; + struct hlist_node hash; GElf_Sym sym; struct section *sec; char *name; - int idx; + unsigned int idx; unsigned char bind, type; unsigned long offset; unsigned int len; @@ -49,10 +53,11 @@ struct symbol { struct rela { struct list_head list; + struct hlist_node hash; GElf_Rela rela; struct symbol *sym; unsigned int type; - int offset; + unsigned long offset; int addend; }; @@ -62,6 +67,7 @@ struct elf { int fd; char *name; struct list_head sections; + DECLARE_HASHTABLE(rela_hash, 16); }; From 1bcb58a099938c33acda78b212ed67b06b3359ef Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 9 Mar 2016 00:07:01 -0600 Subject: [PATCH 52/52] objtool: Only print one warning per function When objtool discovers an issue, it's very common for it to flood the terminal with a lot of duplicate warnings. For example: warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch warning: objtool: rtlwifi_rate_mapping()+0x2f3: frame pointer state mismatch warning: objtool: rtlwifi_rate_mapping()+0x2ff: frame pointer state mismatch warning: objtool: rtlwifi_rate_mapping()+0x30b: frame pointer state mismatch ... The first warning is usually all you need. Change it to only warn once per function. Suggested-by: Ingo Molnar Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/c47f3ca38aa01e2a9b6601f9e38efd414c3f3c18.1457502970.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- tools/objtool/builtin-check.c | 48 ++++++++++++++++++----------------- 1 file changed, 25 insertions(+), 23 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index bfeee227aaab..7515cb2e879a 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -800,7 +800,7 @@ static int validate_branch(struct objtool_file *file, struct instruction *insn; struct section *sec; unsigned char state; - int ret, warnings = 0; + int ret; insn = first; sec = insn->sec; @@ -809,7 +809,7 @@ static int validate_branch(struct objtool_file *file, if (insn->alt_group && list_empty(&insn->alts)) { WARN_FUNC("don't know how to handle branch to middle of alternative instruction group", sec, insn->offset); - warnings++; + return 1; } while (1) { @@ -817,10 +817,10 @@ static int validate_branch(struct objtool_file *file, if (frame_state(insn->state) != frame_state(state)) { WARN_FUNC("frame pointer state mismatch", sec, insn->offset); - warnings++; + return 1; } - return warnings; + return 0; } /* @@ -828,14 +828,15 @@ static int validate_branch(struct objtool_file *file, * the next function. */ if (is_fentry_call(insn) && (state & STATE_FENTRY)) - return warnings; + return 0; insn->visited = true; insn->state = state; list_for_each_entry(alt, &insn->alts, list) { ret = validate_branch(file, alt->insn, state); - warnings += ret; + if (ret) + return 1; } switch (insn->type) { @@ -845,7 +846,7 @@ static int validate_branch(struct objtool_file *file, if (state & STATE_FP_SAVED) { WARN_FUNC("duplicate frame pointer save", sec, insn->offset); - warnings++; + return 1; } state |= STATE_FP_SAVED; } @@ -856,7 +857,7 @@ static int validate_branch(struct objtool_file *file, if (state & STATE_FP_SETUP) { WARN_FUNC("duplicate frame pointer setup", sec, insn->offset); - warnings++; + return 1; } state |= STATE_FP_SETUP; } @@ -875,9 +876,9 @@ static int validate_branch(struct objtool_file *file, if (!nofp && has_modified_stack_frame(insn)) { WARN_FUNC("return without frame pointer restore", sec, insn->offset); - warnings++; + return 1; } - return warnings; + return 0; case INSN_CALL: if (is_fentry_call(insn)) { @@ -887,16 +888,16 @@ static int validate_branch(struct objtool_file *file, ret = dead_end_function(file, insn->call_dest); if (ret == 1) - return warnings; + return 0; if (ret == -1) - warnings++; + return 1; /* fallthrough */ case INSN_CALL_DYNAMIC: if (!nofp && !has_valid_stack_frame(insn)) { WARN_FUNC("call without frame pointer save/setup", sec, insn->offset); - warnings++; + return 1; } break; @@ -905,15 +906,16 @@ static int validate_branch(struct objtool_file *file, if (insn->jump_dest) { ret = validate_branch(file, insn->jump_dest, state); - warnings += ret; + if (ret) + return 1; } else if (has_modified_stack_frame(insn)) { WARN_FUNC("sibling call from callable instruction with changed frame pointer", sec, insn->offset); - warnings++; + return 1; } /* else it's a sibling call */ if (insn->type == INSN_JUMP_UNCONDITIONAL) - return warnings; + return 0; break; @@ -922,13 +924,13 @@ static int validate_branch(struct objtool_file *file, has_modified_stack_frame(insn)) { WARN_FUNC("sibling call from callable instruction with changed frame pointer", sec, insn->offset); - warnings++; + return 1; } - return warnings; + return 0; case INSN_BUG: - return warnings; + return 0; default: break; @@ -937,12 +939,11 @@ static int validate_branch(struct objtool_file *file, insn = next_insn_same_sec(file, insn); if (!insn) { WARN("%s: unexpected end of section", sec->name); - warnings++; - return warnings; + return 1; } } - return warnings; + return 0; } static bool is_gcov_insn(struct instruction *insn) @@ -1055,7 +1056,8 @@ static int validate_functions(struct objtool_file *file) if (insn->visited) continue; - if (!ignore_unreachable_insn(func, insn)) { + if (!ignore_unreachable_insn(func, insn) && + !warnings) { WARN_FUNC("function has unreachable instruction", insn->sec, insn->offset); warnings++; }