Created attachment 306305 [details] .config Noticed a few issues when running Software Tag-Based KASAN with GCC 13: 1. There's a boot-time KASAN report coming from smp_build_mpidr_hash. The code looks legit, so it's likely either a compiler bug or missing KASAN annotations. 2. The kmalloc_memmove_negative_size KASAN Kunit test hangs. Also either a compiler bug or some missing annotations related to CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX. 3. With CONFIG_FORTIFY_SOURCE enabled (and [1] applied to pass memmove/memset/memcpy tests), kasan_strings tests fails. Might also be a compiler issue. Both Clang + KASAN_SW_TAGS and GCC 13 + KASAN_GENERIC combinations work fine. .config for reproducing is attached. For #3, also enable CONFIG_FORTIFY_SOURCE. [1] https://lore.kernel.org/linux-mm/20240517130118.759301-1-andrey.konovalov@linux.dev/T/#u
Mark Rutland posted a detailed analysis for issue #1: https://lore.kernel.org/all/ZvFGwKfoC4yVjN_X@J2N7QTR9R3/
" I believe this is a compiler bug, as there doesn't seem to be a separate attribute to prevent instrumentation in this mode. " At least the above is not true. `__attribute__((no_sanitize("hwaddress")))` and `__attribute__((no_sanitize("kernel-hwaddress")))` Turns off hwasan for the function for GCC.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117196