kasan, fortify: properly rename memintrinsics

After commit 69d4c0d321 ("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: 69d4c0d321 ("entry, kasan, x86: Disallow overriding mem*() functions")
Fixes: 51287dcb00 ("kasan: emit different calls for instrumentable memintrinsics")
Fixes: 36be5cba99 ("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>
This commit is contained in:
Andrey Konovalov 2024-05-17 15:01:18 +02:00 committed by Andrew Morton
parent a38568a0b4
commit 2e577732e8
1 changed files with 18 additions and 4 deletions

View File

@ -75,17 +75,30 @@ void __write_overflow_field(size_t avail, size_t wanted) __compiletime_warning("
__ret; \
})
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
#if defined(__SANITIZE_ADDRESS__)
#if !defined(CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX) && !defined(CONFIG_GENERIC_ENTRY)
extern void *__underlying_memset(void *p, int c, __kernel_size_t size) __RENAME(memset);
extern void *__underlying_memmove(void *p, const void *q, __kernel_size_t size) __RENAME(memmove);
extern void *__underlying_memcpy(void *p, const void *q, __kernel_size_t size) __RENAME(memcpy);
#elif defined(CONFIG_KASAN_GENERIC)
extern void *__underlying_memset(void *p, int c, __kernel_size_t size) __RENAME(__asan_memset);
extern void *__underlying_memmove(void *p, const void *q, __kernel_size_t size) __RENAME(__asan_memmove);
extern void *__underlying_memcpy(void *p, const void *q, __kernel_size_t size) __RENAME(__asan_memcpy);
#else /* CONFIG_KASAN_SW_TAGS */
extern void *__underlying_memset(void *p, int c, __kernel_size_t size) __RENAME(__hwasan_memset);
extern void *__underlying_memmove(void *p, const void *q, __kernel_size_t size) __RENAME(__hwasan_memmove);
extern void *__underlying_memcpy(void *p, const void *q, __kernel_size_t size) __RENAME(__hwasan_memcpy);
#endif
extern void *__underlying_memchr(const void *p, int c, __kernel_size_t size) __RENAME(memchr);
extern int __underlying_memcmp(const void *p, const void *q, __kernel_size_t size) __RENAME(memcmp);
extern void *__underlying_memcpy(void *p, const void *q, __kernel_size_t size) __RENAME(memcpy);
extern void *__underlying_memmove(void *p, const void *q, __kernel_size_t size) __RENAME(memmove);
extern void *__underlying_memset(void *p, int c, __kernel_size_t size) __RENAME(memset);
extern char *__underlying_strcat(char *p, const char *q) __RENAME(strcat);
extern char *__underlying_strcpy(char *p, const char *q) __RENAME(strcpy);
extern __kernel_size_t __underlying_strlen(const char *p) __RENAME(strlen);
extern char *__underlying_strncat(char *p, const char *q, __kernel_size_t count) __RENAME(strncat);
extern char *__underlying_strncpy(char *p, const char *q, __kernel_size_t size) __RENAME(strncpy);
#else
#if defined(__SANITIZE_MEMORY__)
@ -110,6 +123,7 @@ extern char *__underlying_strncpy(char *p, const char *q, __kernel_size_t size)
#define __underlying_strlen __builtin_strlen
#define __underlying_strncat __builtin_strncat
#define __underlying_strncpy __builtin_strncpy
#endif
/**