Re: [PATCH -tip v4 4/4] kasan, x86: Don't rename memintrinsics in uninstrumented files

[Andrey Konovalov]

On Fri, Feb 17, 2023 at 1:53 PM Marco Elver <elver@xxxxxxxxxx> wrote:
>
> Now that memcpy/memset/memmove are no longer overridden by KASAN, we can
> just use the normal symbol names in uninstrumented files.
>
> Drop the preprocessor redefinitions.
>
> Fixes: 69d4c0d32186 ("entry, kasan, x86: Disallow overriding mem*() functions")
> Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
> ---
> v4:
> * New patch.
> ---
>  arch/x86/include/asm/string_64.h | 19 -------------------
>  1 file changed, 19 deletions(-)
>
> diff --git a/arch/x86/include/asm/string_64.h b/arch/x86/include/asm/string_64.h
> index 888731ccf1f6..c1e14cee0722 100644
> --- a/arch/x86/include/asm/string_64.h
> +++ b/arch/x86/include/asm/string_64.h
> @@ -85,25 +85,6 @@ char *strcpy(char *dest, const char *src);
>  char *strcat(char *dest, const char *src);
>  int strcmp(const char *cs, const char *ct);
>
> -#if (defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__))
> -/*
> - * For files that not instrumented (e.g. mm/slub.c) we
> - * should use not instrumented version of mem* functions.
> - */
> -
> -#undef memcpy
> -#define memcpy(dst, src, len) __memcpy(dst, src, len)
> -#undef memmove
> -#define memmove(dst, src, len) __memmove(dst, src, len)
> -#undef memset
> -#define memset(s, c, n) __memset(s, c, n)
> -
> -#ifndef __NO_FORTIFY
> -#define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
> -#endif
> -
> -#endif
> -
>  #ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
>  #define __HAVE_ARCH_MEMCPY_FLUSHCACHE 1
>  void __memcpy_flushcache(void *dst, const void *src, size_t cnt);
> --
> 2.39.2.637.g21b0678d19-goog
>

Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxx>

Thank you, Marco!