kernel-fxtec-pro1x/security/Kconfig.hardening

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# SPDX-License-Identifier: GPL-2.0-only
menu "Kernel hardening options"
config GCC_PLUGIN_STRUCTLEAK
bool "Force initialization of variables containing userspace addresses"
# Currently STRUCTLEAK inserts initialization out of live scope of
# variables from KASAN point of view. This leads to KASAN false
# positive reports. Prohibit this combination for now.
depends on !KASAN_EXTRA
help
This plugin zero-initializes any structures containing a
__user attribute. This can prevent some classes of information
exposures.
This plugin was ported from grsecurity/PaX. More information at:
* https://grsecurity.net/
* https://pax.grsecurity.net/
menu "Memory initialization"
UPSTREAM: security: Implement Clang's stack initialization CONFIG_INIT_STACK_ALL turns on stack initialization based on -ftrivial-auto-var-init in Clang builds, which has greater coverage than CONFIG_GCC_PLUGINS_STRUCTLEAK_BYREF_ALL. -ftrivial-auto-var-init Clang option provides trivial initializers for uninitialized local variables, variable fields and padding. It has three possible values: pattern - uninitialized locals are filled with a fixed pattern (mostly 0xAA on 64-bit platforms, see https://reviews.llvm.org/D54604 for more details, but 0x000000AA for 32-bit pointers) likely to cause crashes when uninitialized value is used; zero (it's still debated whether this flag makes it to the official Clang release) - uninitialized locals are filled with zeroes; uninitialized (default) - uninitialized locals are left intact. This patch uses only the "pattern" mode when CONFIG_INIT_STACK_ALL is enabled. Developers have the possibility to opt-out of this feature on a per-variable basis by using __attribute__((uninitialized)), but such use should be well justified in comments. Change-Id: I3ae7ade50c55fa6b88e8eed23942f09530ceb0e7 Co-developed-by: Alexander Potapenko <glider@google.com> Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Alexander Potapenko <glider@google.com> Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> (cherry picked from commit 709a972efb01efaeb97cad1adc87fe400119c8ab) Bug: 133428616 Signed-off-by: Alexander Potapenko <glider@google.com>
2019-04-10 09:48:31 -06:00
config CC_HAS_AUTO_VAR_INIT
def_bool $(cc-option,-ftrivial-auto-var-init=pattern)
choice
prompt "Initialize kernel stack variables at function entry"
default GCC_PLUGIN_STRUCTLEAK_BYREF_ALL if COMPILE_TEST && GCC_PLUGINS
UPSTREAM: security: Implement Clang's stack initialization CONFIG_INIT_STACK_ALL turns on stack initialization based on -ftrivial-auto-var-init in Clang builds, which has greater coverage than CONFIG_GCC_PLUGINS_STRUCTLEAK_BYREF_ALL. -ftrivial-auto-var-init Clang option provides trivial initializers for uninitialized local variables, variable fields and padding. It has three possible values: pattern - uninitialized locals are filled with a fixed pattern (mostly 0xAA on 64-bit platforms, see https://reviews.llvm.org/D54604 for more details, but 0x000000AA for 32-bit pointers) likely to cause crashes when uninitialized value is used; zero (it's still debated whether this flag makes it to the official Clang release) - uninitialized locals are filled with zeroes; uninitialized (default) - uninitialized locals are left intact. This patch uses only the "pattern" mode when CONFIG_INIT_STACK_ALL is enabled. Developers have the possibility to opt-out of this feature on a per-variable basis by using __attribute__((uninitialized)), but such use should be well justified in comments. Change-Id: I3ae7ade50c55fa6b88e8eed23942f09530ceb0e7 Co-developed-by: Alexander Potapenko <glider@google.com> Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Alexander Potapenko <glider@google.com> Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> (cherry picked from commit 709a972efb01efaeb97cad1adc87fe400119c8ab) Bug: 133428616 Signed-off-by: Alexander Potapenko <glider@google.com>
2019-04-10 09:48:31 -06:00
default INIT_STACK_ALL if COMPILE_TEST && CC_HAS_AUTO_VAR_INIT
default INIT_STACK_NONE
help
This option enables initialization of stack variables at
function entry time. This has the possibility to have the
greatest coverage (since all functions can have their
variables initialized), but the performance impact depends
on the function calling complexity of a given workload's
syscalls.
This chooses the level of coverage over classes of potentially
uninitialized variables. The selected class will be
initialized before use in a function.
config INIT_STACK_NONE
bool "no automatic initialization (weakest)"
help
Disable automatic stack variable initialization.
This leaves the kernel vulnerable to the standard
classes of uninitialized stack variable exploits
and information exposures.
config GCC_PLUGIN_STRUCTLEAK_BYREF_ALL
bool "Force initialize all struct type variables passed by reference"
depends on GCC_PLUGIN_STRUCTLEAK
depends on !COMPILE_TEST
help
Zero initialize any struct type local variable that may
be passed by reference without having been initialized.
UPSTREAM: security: Implement Clang's stack initialization CONFIG_INIT_STACK_ALL turns on stack initialization based on -ftrivial-auto-var-init in Clang builds, which has greater coverage than CONFIG_GCC_PLUGINS_STRUCTLEAK_BYREF_ALL. -ftrivial-auto-var-init Clang option provides trivial initializers for uninitialized local variables, variable fields and padding. It has three possible values: pattern - uninitialized locals are filled with a fixed pattern (mostly 0xAA on 64-bit platforms, see https://reviews.llvm.org/D54604 for more details, but 0x000000AA for 32-bit pointers) likely to cause crashes when uninitialized value is used; zero (it's still debated whether this flag makes it to the official Clang release) - uninitialized locals are filled with zeroes; uninitialized (default) - uninitialized locals are left intact. This patch uses only the "pattern" mode when CONFIG_INIT_STACK_ALL is enabled. Developers have the possibility to opt-out of this feature on a per-variable basis by using __attribute__((uninitialized)), but such use should be well justified in comments. Change-Id: I3ae7ade50c55fa6b88e8eed23942f09530ceb0e7 Co-developed-by: Alexander Potapenko <glider@google.com> Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Alexander Potapenko <glider@google.com> Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> (cherry picked from commit 709a972efb01efaeb97cad1adc87fe400119c8ab) Bug: 133428616 Signed-off-by: Alexander Potapenko <glider@google.com>
2019-04-10 09:48:31 -06:00
config INIT_STACK_ALL
bool "0xAA-init everything on the stack (strongest)"
depends on CC_HAS_AUTO_VAR_INIT
help
Initializes everything on the stack with a 0xAA
pattern. This is intended to eliminate all classes
of uninitialized stack variable exploits and information
exposures, even variables that were warned to have been
left uninitialized.
endchoice
config GCC_PLUGIN_STRUCTLEAK_VERBOSE
bool "Report forcefully initialized variables"
depends on GCC_PLUGIN_STRUCTLEAK
depends on !COMPILE_TEST # too noisy
help
This option will cause a warning to be printed each time the
structleak plugin finds a variable it thinks needs to be
initialized. Since not all existing initializers are detected
by the plugin, this can produce false positive warnings.
endmenu
endmenu