diff options
| author | Jan Hendrik Farr <kernel@jfarr.cc> | 2024-10-29 15:00:36 +0100 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2024-11-19 08:48:27 -0800 |
| commit | f06e108a3dc53c0f5234d18de0bd224753db5019 (patch) | |
| tree | dfd005f49520b03268194bd63890791605a016d4 /init | |
| parent | d7a516c6eeae29144649f1c3f586fa580ec9e040 (diff) | |
Compiler Attributes: disable __counted_by for clang < 19.1.3
This patch disables __counted_by for clang versions < 19.1.3 because
of the two issues listed below. It does this by introducing
CONFIG_CC_HAS_COUNTED_BY.
1. clang < 19.1.2 has a bug that can lead to __bdos returning 0:
https://github.com/llvm/llvm-project/pull/110497
2. clang < 19.1.3 has a bug that can lead to __bdos being off by 4:
https://github.com/llvm/llvm-project/pull/112636
Fixes: c8248faf3ca2 ("Compiler Attributes: counted_by: Adjust name and identifier expansion")
Cc: stable@vger.kernel.org # 6.6.x: 16c31dd7fdf6: Compiler Attributes: counted_by: bump min gcc version
Cc: stable@vger.kernel.org # 6.6.x: 2993eb7a8d34: Compiler Attributes: counted_by: fixup clang URL
Cc: stable@vger.kernel.org # 6.6.x: 231dc3f0c936: lkdtm/bugs: Improve warning message for compilers without counted_by support
Cc: stable@vger.kernel.org # 6.6.x
Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/all/20240913164630.GA4091534@thelio-3990X/
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202409260949.a1254989-oliver.sang@intel.com
Link: https://lore.kernel.org/all/Zw8iawAF5W2uzGuh@archlinux/T/#m204c09f63c076586a02d194b87dffc7e81b8de7b
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Jan Hendrik Farr <kernel@jfarr.cc>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Thorsten Blum <thorsten.blum@linux.dev>
Link: https://lore.kernel.org/r/20241029140036.577804-2-kernel@jfarr.cc
Signed-off-by: Kees Cook <kees@kernel.org>
Diffstat (limited to 'init')
| -rw-r--r-- | init/Kconfig | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/init/Kconfig b/init/Kconfig index 530a382ee0fe..92f106cf5572 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -116,6 +116,15 @@ config CC_HAS_ASM_INLINE config CC_HAS_NO_PROFILE_FN_ATTR def_bool $(success,echo '__attribute__((no_profile_instrument_function)) int x();' | $(CC) -x c - -c -o /dev/null -Werror) +config CC_HAS_COUNTED_BY + # TODO: when gcc 15 is released remove the build test and add + # a gcc version check + def_bool $(success,echo 'struct flex { int count; int array[] __attribute__((__counted_by__(count))); };' | $(CC) $(CLANG_FLAGS) -x c - -c -o /dev/null -Werror) + # clang needs to be at least 19.1.3 to avoid __bdos miscalculations + # https://github.com/llvm/llvm-project/pull/110497 + # https://github.com/llvm/llvm-project/pull/112636 + depends on !(CC_IS_CLANG && CLANG_VERSION < 190103) + config PAHOLE_VERSION int default $(shell,$(srctree)/scripts/pahole-version.sh $(PAHOLE)) |