221af7f87b
'flush_old_exec()' is the point of no return when doing an execve(), and it is pretty badly misnamed. It doesn't just flush the old executable environment, it also starts up the new one. Which is very inconvenient for things like setting up the new personality, because we want the new personality to affect the starting of the new environment, but at the same time we do _not_ want the new personality to take effect if flushing the old one fails. As a result, the x86-64 '32-bit' personality is actually done using this insane "I'm going to change the ABI, but I haven't done it yet" bit (TIF_ABI_PENDING), with SET_PERSONALITY() not actually setting the personality, but just the "pending" bit, so that "flush_thread()" can do the actual personality magic. This patch in no way changes any of that insanity, but it does split the 'flush_old_exec()' function up into a preparatory part that can fail (still called flush_old_exec()), and a new part that will actually set up the new exec environment (setup_new_exec()). All callers are changed to trivially comply with the new world order. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
136 lines
4.3 KiB
C
136 lines
4.3 KiB
C
#ifndef _LINUX_BINFMTS_H
|
|
#define _LINUX_BINFMTS_H
|
|
|
|
#include <linux/capability.h>
|
|
|
|
struct pt_regs;
|
|
|
|
/*
|
|
* These are the maximum length and maximum number of strings passed to the
|
|
* execve() system call. MAX_ARG_STRLEN is essentially random but serves to
|
|
* prevent the kernel from being unduly impacted by misaddressed pointers.
|
|
* MAX_ARG_STRINGS is chosen to fit in a signed 32-bit integer.
|
|
*/
|
|
#define MAX_ARG_STRLEN (PAGE_SIZE * 32)
|
|
#define MAX_ARG_STRINGS 0x7FFFFFFF
|
|
|
|
/* sizeof(linux_binprm->buf) */
|
|
#define BINPRM_BUF_SIZE 128
|
|
|
|
#ifdef __KERNEL__
|
|
#include <linux/list.h>
|
|
|
|
#define CORENAME_MAX_SIZE 128
|
|
|
|
/*
|
|
* This structure is used to hold the arguments that are used when loading binaries.
|
|
*/
|
|
struct linux_binprm{
|
|
char buf[BINPRM_BUF_SIZE];
|
|
#ifdef CONFIG_MMU
|
|
struct vm_area_struct *vma;
|
|
#else
|
|
# define MAX_ARG_PAGES 32
|
|
struct page *page[MAX_ARG_PAGES];
|
|
#endif
|
|
struct mm_struct *mm;
|
|
unsigned long p; /* current top of mem */
|
|
unsigned int
|
|
cred_prepared:1,/* true if creds already prepared (multiple
|
|
* preps happen for interpreters) */
|
|
cap_effective:1;/* true if has elevated effective capabilities,
|
|
* false if not; except for init which inherits
|
|
* its parent's caps anyway */
|
|
#ifdef __alpha__
|
|
unsigned int taso:1;
|
|
#endif
|
|
unsigned int recursion_depth;
|
|
struct file * file;
|
|
struct cred *cred; /* new credentials */
|
|
int unsafe; /* how unsafe this exec is (mask of LSM_UNSAFE_*) */
|
|
unsigned int per_clear; /* bits to clear in current->personality */
|
|
int argc, envc;
|
|
char * filename; /* Name of binary as seen by procps */
|
|
char * interp; /* Name of the binary really executed. Most
|
|
of the time same as filename, but could be
|
|
different for binfmt_{misc,script} */
|
|
unsigned interp_flags;
|
|
unsigned interp_data;
|
|
unsigned long loader, exec;
|
|
};
|
|
|
|
#define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
|
|
#define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
|
|
|
|
/* fd of the binary should be passed to the interpreter */
|
|
#define BINPRM_FLAGS_EXECFD_BIT 1
|
|
#define BINPRM_FLAGS_EXECFD (1 << BINPRM_FLAGS_EXECFD_BIT)
|
|
|
|
#define BINPRM_MAX_RECURSION 4
|
|
|
|
/* Function parameter for binfmt->coredump */
|
|
struct coredump_params {
|
|
long signr;
|
|
struct pt_regs *regs;
|
|
struct file *file;
|
|
unsigned long limit;
|
|
};
|
|
|
|
/*
|
|
* This structure defines the functions that are used to load the binary formats that
|
|
* linux accepts.
|
|
*/
|
|
struct linux_binfmt {
|
|
struct list_head lh;
|
|
struct module *module;
|
|
int (*load_binary)(struct linux_binprm *, struct pt_regs * regs);
|
|
int (*load_shlib)(struct file *);
|
|
int (*core_dump)(struct coredump_params *cprm);
|
|
unsigned long min_coredump; /* minimal dump size */
|
|
int hasvdso;
|
|
};
|
|
|
|
extern int __register_binfmt(struct linux_binfmt *fmt, int insert);
|
|
|
|
/* Registration of default binfmt handlers */
|
|
static inline int register_binfmt(struct linux_binfmt *fmt)
|
|
{
|
|
return __register_binfmt(fmt, 0);
|
|
}
|
|
/* Same as above, but adds a new binfmt at the top of the list */
|
|
static inline int insert_binfmt(struct linux_binfmt *fmt)
|
|
{
|
|
return __register_binfmt(fmt, 1);
|
|
}
|
|
|
|
extern void unregister_binfmt(struct linux_binfmt *);
|
|
|
|
extern int prepare_binprm(struct linux_binprm *);
|
|
extern int __must_check remove_arg_zero(struct linux_binprm *);
|
|
extern int search_binary_handler(struct linux_binprm *,struct pt_regs *);
|
|
extern int flush_old_exec(struct linux_binprm * bprm);
|
|
extern void setup_new_exec(struct linux_binprm * bprm);
|
|
|
|
extern int suid_dumpable;
|
|
#define SUID_DUMP_DISABLE 0 /* No setuid dumping */
|
|
#define SUID_DUMP_USER 1 /* Dump as user of process */
|
|
#define SUID_DUMP_ROOT 2 /* Dump as root */
|
|
|
|
/* Stack area protections */
|
|
#define EXSTACK_DEFAULT 0 /* Whatever the arch defaults to */
|
|
#define EXSTACK_DISABLE_X 1 /* Disable executable stacks */
|
|
#define EXSTACK_ENABLE_X 2 /* Enable executable stacks */
|
|
|
|
extern int setup_arg_pages(struct linux_binprm * bprm,
|
|
unsigned long stack_top,
|
|
int executable_stack);
|
|
extern int bprm_mm_init(struct linux_binprm *bprm);
|
|
extern int copy_strings_kernel(int argc,char ** argv,struct linux_binprm *bprm);
|
|
extern int prepare_bprm_creds(struct linux_binprm *bprm);
|
|
extern void install_exec_creds(struct linux_binprm *bprm);
|
|
extern void do_coredump(long signr, int exit_code, struct pt_regs *regs);
|
|
extern void set_binfmt(struct linux_binfmt *new);
|
|
extern void free_bprm(struct linux_binprm *);
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _LINUX_BINFMTS_H */
|