kasan, fortify: properly rename memintrinsics

After commit 69d4c0d32186 ("entry, kasan, x86: Disallow overriding mem*()
functions") and the follow-up fixes, with CONFIG_FORTIFY_SOURCE enabled,
even though the compiler instruments meminstrinsics by generating calls to
__asan/__hwasan_ prefixed functions, FORTIFY_SOURCE still uses
uninstrumented memset/memmove/memcpy as the underlying functions.

As a result, KASAN cannot detect bad accesses in memset/memmove/memcpy.
This also makes KASAN tests corrupt kernel memory and cause crashes.

To fix this, use __asan_/__hwasan_memset/memmove/memcpy as the underlying
functions whenever appropriate. Do this only for the instrumented code
(as indicated by __SANITIZE_ADDRESS__).

Link: https://lkml.kernel.org/r/20240517130118.759301-1-andrey.konovalov@linux.dev
Fixes: 69d4c0d32186 ("entry, kasan, x86: Disallow overriding mem*() functions")
Fixes: 51287dcb00cc ("kasan: emit different calls for instrumentable memintrinsics")
Fixes: 36be5cba99f6 ("kasan: treat meminstrinsic as builtins in uninstrumented files")
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Reported-by: Nico Pache <npache@redhat.com>
Closes: https://lore.kernel.org/all/20240501144156.17e65021@outsider.home/
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Nico Pache <npache@redhat.com>
Acked-by: Nico Pache <npache@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

authored by Andrey Konovalov and committed by Andrew Morton 2e577732 a38568a0

+18 -4
+18 -4
include/linux/fortify-string.h
··· 75 75 __ret; \ 76 76 }) 77 77 78 - #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 78 + #if defined(__SANITIZE_ADDRESS__) 79 + 80 + #if !defined(CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX) && !defined(CONFIG_GENERIC_ENTRY) 81 + extern void *__underlying_memset(void *p, int c, __kernel_size_t size) __RENAME(memset); 82 + extern void *__underlying_memmove(void *p, const void *q, __kernel_size_t size) __RENAME(memmove); 83 + extern void *__underlying_memcpy(void *p, const void *q, __kernel_size_t size) __RENAME(memcpy); 84 + #elif defined(CONFIG_KASAN_GENERIC) 85 + extern void *__underlying_memset(void *p, int c, __kernel_size_t size) __RENAME(__asan_memset); 86 + extern void *__underlying_memmove(void *p, const void *q, __kernel_size_t size) __RENAME(__asan_memmove); 87 + extern void *__underlying_memcpy(void *p, const void *q, __kernel_size_t size) __RENAME(__asan_memcpy); 88 + #else /* CONFIG_KASAN_SW_TAGS */ 89 + extern void *__underlying_memset(void *p, int c, __kernel_size_t size) __RENAME(__hwasan_memset); 90 + extern void *__underlying_memmove(void *p, const void *q, __kernel_size_t size) __RENAME(__hwasan_memmove); 91 + extern void *__underlying_memcpy(void *p, const void *q, __kernel_size_t size) __RENAME(__hwasan_memcpy); 92 + #endif 93 + 79 94 extern void *__underlying_memchr(const void *p, int c, __kernel_size_t size) __RENAME(memchr); 80 95 extern int __underlying_memcmp(const void *p, const void *q, __kernel_size_t size) __RENAME(memcmp); 81 - extern void *__underlying_memcpy(void *p, const void *q, __kernel_size_t size) __RENAME(memcpy); 82 - extern void *__underlying_memmove(void *p, const void *q, __kernel_size_t size) __RENAME(memmove); 83 - extern void *__underlying_memset(void *p, int c, __kernel_size_t size) __RENAME(memset); 84 96 extern char *__underlying_strcat(char *p, const char *q) __RENAME(strcat); 85 97 extern char *__underlying_strcpy(char *p, const char *q) __RENAME(strcpy); 86 98 extern __kernel_size_t __underlying_strlen(const char *p) __RENAME(strlen); 87 99 extern char *__underlying_strncat(char *p, const char *q, __kernel_size_t count) __RENAME(strncat); 88 100 extern char *__underlying_strncpy(char *p, const char *q, __kernel_size_t size) __RENAME(strncpy); 101 + 89 102 #else 90 103 91 104 #if defined(__SANITIZE_MEMORY__) ··· 123 110 #define __underlying_strlen __builtin_strlen 124 111 #define __underlying_strncat __builtin_strncat 125 112 #define __underlying_strncpy __builtin_strncpy 113 + 126 114 #endif 127 115 128 116 /**