Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2024-12-29 17:22:07 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

ubsan: remove CONFIG_UBSAN_OBJECT_SIZE

Browse Source 
The object-size sanitizer is redundant to -Warray-bounds, and
inappropriately performs its checks at run-time when all information
needed for the evaluation is available at compile-time, making it quite
difficult to use:

  https://bugzilla.kernel.org/show_bug.cgi?id=214861

With -Warray-bounds almost enabled globally, it doesn't make sense to
keep this around.

Link: https://lkml.kernel.org/r/20211203235346.110809-1-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Kees Cook 2022-01-19 18:10:35 -08:00 committed by Linus Torvalds
parent bece04b5b4
commit 69d0db01e2
3 changed files with 0 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
lib/Kconfig.ubsan
View File

@ -112,19 +112,6 @@ config UBSAN_UNREACHABLE
This option enables -fsanitize=unreachable which checks for control
flow reaching an expected-to-be-unreachable position.
config UBSAN_OBJECT_SIZE
bool "Perform checking for accesses beyond the end of objects"
default UBSAN
# gcc hugely expands stack usage with -fsanitize=object-size
# https://lore.kernel.org/lkml/CAHk-=wjPasyJrDuwDnpHJS2TuQfExwe=px-SzLeN8GFMAQJPmQ@mail.gmail.com/
depends on !CC_IS_GCC
depends on $(cc-option,-fsanitize=object-size)
help
This option enables -fsanitize=object-size which checks for accesses
beyond the end of objects where the optimizer can determine both the
object being operated on and its size, usually seen with bad downcasts,
or access to struct members from NULL pointers.
config UBSAN_BOOL
bool "Perform checking for non-boolean values used as boolean"
default UBSAN

22
lib/test_ubsan.c
View File

@ -79,15 +79,6 @@ static void test_ubsan_load_invalid_value(void)
eval2 = eval;
}
static void test_ubsan_null_ptr_deref(void)
{
volatile int *ptr = NULL;
int val;
UBSAN_TEST(CONFIG_UBSAN_OBJECT_SIZE);
val = *ptr;
}
static void test_ubsan_misaligned_access(void)
{
volatile char arr[5] __aligned(4) = {1, 2, 3, 4, 5};
@ -98,29 +89,16 @@ static void test_ubsan_misaligned_access(void)
*ptr = val;
}
static void test_ubsan_object_size_mismatch(void)
{
/* "((aligned(8)))" helps this not into be misaligned for ptr-access. */
volatile int val __aligned(8) = 4;
volatile long long *ptr, val2;
UBSAN_TEST(CONFIG_UBSAN_OBJECT_SIZE);
ptr = (long long *)&val;
val2 = *ptr;
}
static const test_ubsan_fp test_ubsan_array[] = {
test_ubsan_shift_out_of_bounds,
test_ubsan_out_of_bounds,
test_ubsan_load_invalid_value,
test_ubsan_misaligned_access,
test_ubsan_object_size_mismatch,
};
/* Excluded because they Oops the module. */
static const test_ubsan_fp skip_ubsan_array[] = {
test_ubsan_divrem_overflow,
test_ubsan_null_ptr_deref,
};
static int __init test_ubsan_init(void)

1
scripts/Makefile.ubsan
View File

@ -8,7 +8,6 @@ ubsan-cflags-$(CONFIG_UBSAN_LOCAL_BOUNDS) += -fsanitize=local-bounds
ubsan-cflags-$(CONFIG_UBSAN_SHIFT) += -fsanitize=shift
ubsan-cflags-$(CONFIG_UBSAN_DIV_ZERO) += -fsanitize=integer-divide-by-zero
ubsan-cflags-$(CONFIG_UBSAN_UNREACHABLE) += -fsanitize=unreachable
ubsan-cflags-$(CONFIG_UBSAN_OBJECT_SIZE) += -fsanitize=object-size
ubsan-cflags-$(CONFIG_UBSAN_BOOL) += -fsanitize=bool
ubsan-cflags-$(CONFIG_UBSAN_ENUM) += -fsanitize=enum
ubsan-cflags-$(CONFIG_UBSAN_TRAP) += -fsanitize-undefined-trap-on-error