The quilt patch titled Subject: kasan: fix GCC mem-intrinsic prefix with sw tags has been removed from the -mm tree. Its filename was kasan-fix-gcc-mem-intrinsic-prefix-with-sw-tags.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------ From: Ada Couprie Diaz ada.coupriediaz@arm.com Subject: kasan: fix GCC mem-intrinsic prefix with sw tags Date: Thu, 21 Aug 2025 13:07:35 +0100
GCC doesn't support "hwasan-kernel-mem-intrinsic-prefix", only "asan-kernel-mem-intrinsic-prefix"[0], while LLVM supports both. This is already taken into account when checking "CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX", but not in the KASAN Makefile adding those parameters when "CONFIG_KASAN_SW_TAGS" is enabled.
Replace the version check with "CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX", which already validates that mem-intrinsic prefix parameter can be used, and choose the correct name depending on compiler.
GCC 13 and above trigger "CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX" which prevents `mem{cpy,move,set}()` being redefined in "mm/kasan/shadow.c" since commit 36be5cba99f6 ("kasan: treat meminstrinsic as builtins in uninstrumented files"), as we expect the compiler to prefix those calls with `__(hw)asan_` instead. But as the option passed to GCC has been incorrect, the compiler has not been emitting those prefixes, effectively never calling the instrumented versions of `mem{cpy,move,set}()` with "CONFIG_KASAN_SW_TAGS" enabled.
If "CONFIG_FORTIFY_SOURCES" is enabled, this issue would be mitigated as it redefines `mem{cpy,move,set}()` and properly aliases the `__underlying_mem*()` that will be called to the instrumented versions.
Link: https://lkml.kernel.org/r/20250821120735.156244-1-ada.coupriediaz@arm.com Link: https://gcc.gnu.org/onlinedocs/gcc-13.4.0/gcc/Optimize-Options.html [0] Signed-off-by: Ada Couprie Diaz ada.coupriediaz@arm.com Fixes: 36be5cba99f6 ("kasan: treat meminstrinsic as builtins in uninstrumented files") Reviewed-by: Yeoreum Yun yeoreum.yun@arm.com Cc: Alexander Potapenko glider@google.com Cc: Andrey Konovalov andreyknvl@gmail.com Cc: Andrey Ryabinin ryabinin.a.a@gmail.com Cc: Dmitriy Vyukov dvyukov@google.com Cc: Marco Elver elver@google.com Cc: Marc Rutland mark.rutland@arm.com Cc: Michael Ellerman mpe@ellerman.id.au Cc: Nathan Chancellor nathan@kernel.org Cc: Vincenzo Frascino vincenzo.frascino@arm.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
scripts/Makefile.kasan | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
--- a/scripts/Makefile.kasan~kasan-fix-gcc-mem-intrinsic-prefix-with-sw-tags +++ a/scripts/Makefile.kasan @@ -86,10 +86,14 @@ kasan_params += hwasan-instrument-stack= hwasan-use-short-granules=0 \ hwasan-inline-all-checks=0
-# Instrument memcpy/memset/memmove calls by using instrumented __hwasan_mem*(). -ifeq ($(call clang-min-version, 150000)$(call gcc-min-version, 130000),y) - kasan_params += hwasan-kernel-mem-intrinsic-prefix=1 -endif +# Instrument memcpy/memset/memmove calls by using instrumented __(hw)asan_mem*(). +ifdef CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX + ifdef CONFIG_CC_IS_GCC + kasan_params += asan-kernel-mem-intrinsic-prefix=1 + else + kasan_params += hwasan-kernel-mem-intrinsic-prefix=1 + endif +endif # CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX
endif # CONFIG_KASAN_SW_TAGS
_
Patches currently in -mm which might be from ada.coupriediaz@arm.com are