Kees Cook 439a1bcac6 fortify: Use __builtin_dynamic_object_size() when available ... Since the commits starting with c37495d625 ("slab: add __alloc_size attributes for better bounds checking"), the compilers have runtime allocation size hints available in some places. This was immediately available to CONFIG_UBSAN_BOUNDS, but CONFIG_FORTIFY_SOURCE needed updating to explicitly make use of the hints via the associated __builtin_dynamic_object_size() helper. Detect and use the builtin when it is available, increasing the accuracy of the mitigation. When runtime sizes are not available, __builtin_dynamic_object_size() falls back to __builtin_object_size(), leaving the existing bounds checking unchanged. Additionally update the VMALLOC_LINEAR_OVERFLOW LKDTM test to make the hint invisible, otherwise the architectural defense is not exercised (the buffer overflow is detected in the memset() rather than when it crosses the edge of the allocation). Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Tom Rix <trix@redhat.com> Cc: linux-hardening@vger.kernel.org Cc: llvm@lists.linux.dev Reviewed-by: Miguel Ojeda <ojeda@kernel.org> # include/linux/compiler_attributes.h Signed-off-by: Kees Cook <keescook@chromium.org>		2023-01-05 12:08:29 -08:00
..
bugs.c	drivers: lkdtm: fix clang -Wformat warning	2022-07-28 16:20:36 +02:00
cfi.c	lkdtm: cfi: Make PAC test work with GCC 7 and 8	2022-12-14 16:05:09 -08:00
core.c	lkdtm: Move crashtype definitions into each category	2022-04-12 16:16:48 -07:00
fortify.c	lkdtm: Update tests for memcpy() run-time warnings	2022-09-07 16:37:27 -07:00
heap.c	fortify: Use __builtin_dynamic_object_size() when available	2023-01-05 12:08:29 -08:00
lkdtm.h	lkdtm: Move crashtype definitions into each category	2022-04-12 16:16:48 -07:00
Makefile	lkdtm: Disable return thunks in rodata.c	2022-07-20 19:24:53 +02:00
perms.c	lkdtm: Move crashtype definitions into each category	2022-04-12 16:16:48 -07:00
powerpc.c	lkdtm: Move crashtype definitions into each category	2022-04-12 16:16:48 -07:00
refcount.c	lkdtm: Move crashtype definitions into each category	2022-04-12 16:16:48 -07:00
rodata.c	lkdtm: don't move ctors to .rodata	2020-12-09 15:51:14 +01:00
stackleak.c	Char / Misc / Other smaller driver subsystem updates for 5.19-rc1	2022-06-03 11:36:34 -07:00
usercopy.c	treewide: Drop function_nocfi	2022-09-26 10:13:14 -07:00