> > I'd like to avoid touching per-arch asm/string.h files if possible. > > Can't we do like below (i.e. keep asm implementations as-is, but > automatically redirect to __msan_memset()) ? If yes, we could move all > __msan_*() redirection from per-arch asm/string.h files to the common > linux/string.h file? > > diff --git a/include/linux/string.h b/include/linux/string.h > index c062c581a98b..403813b04e00 100644 > --- a/include/linux/string.h > +++ b/include/linux/string.h > @@ -360,4 +360,15 @@ static __always_inline size_t str_has_prefix(const char *str, const char *prefix > return strncmp(str, prefix, len) == 0 ? len : 0; > } > > +#if defined(__SANITIZE_MEMORY__) && defined(__NO_FORTIFY) > +#undef memset > +#define memset(dest, src, count) __msan_memset((dest), (src), (count)) > +#undef memset16 > +#define memset16(dest, src, count) __msan_memset((dest), (src), (count) << 1) > +#undef memset32 > +#define memset32(dest, src, count) __msan_memset((dest), (src), (count) << 2) > +#undef memset64 > +#define memset64(dest, src, count) __msan_memset((dest), (src), (count) << 3) > +#endif The problem with this approach is that it can only work for memset/memcpy/memmove, whereas any function that is implemented in lib/string.c may require undefining the respective __HAVE_ARCH_FNAME so that KMSAN can instrument it.
