From 27f644dc5a77f8d9ab6d08bc7b95f8631c1530c8 Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Fri, 3 Mar 2023 15:14:32 +0100 Subject: [PATCH] x86: kmsan: use C versions of memset16/memset32/memset64 KMSAN must see as many memory accesses as possible to prevent false positive reports. Fall back to versions of memset16()/memset32()/memset64() implemented in lib/string.c instead of those written in assembly. Link: https://lkml.kernel.org/r/20230303141433.3422671-3-glider@google.com Signed-off-by: Alexander Potapenko Suggested-by: Tetsuo Handa Reviewed-by: Marco Elver Cc: Geert Uytterhoeven Cc: Daniel Vetter Cc: Helge Deller Cc: Kees Cook Signed-off-by: Andrew Morton --- arch/x86/include/asm/string_64.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/include/asm/string_64.h b/arch/x86/include/asm/string_64.h index 65537d8..857d364 100644 --- a/arch/x86/include/asm/string_64.h +++ b/arch/x86/include/asm/string_64.h @@ -22,6 +22,11 @@ extern void *__memcpy(void *to, const void *from, size_t len); void *memset(void *s, int c, size_t n); void *__memset(void *s, int c, size_t n); +/* + * KMSAN needs to instrument as much code as possible. Use C versions of + * memsetXX() from lib/string.c under KMSAN. + */ +#if !defined(CONFIG_KMSAN) #define __HAVE_ARCH_MEMSET16 static inline void *memset16(uint16_t *s, uint16_t v, size_t n) { @@ -57,6 +62,7 @@ static inline void *memset64(uint64_t *s, uint64_t v, size_t n) : "memory"); return s; } +#endif #define __HAVE_ARCH_MEMMOVE void *memmove(void *dest, const void *src, size_t count); -- 2.7.4