diff options
Diffstat (limited to 'mm/kasan')
-rw-r--r-- | mm/kasan/common.c | 11 | ||||
-rw-r--r-- | mm/kasan/generic.c | 4 | ||||
-rw-r--r-- | mm/kasan/kasan.h | 10 | ||||
-rw-r--r-- | mm/kasan/sw_tags.c | 6 |
4 files changed, 20 insertions, 11 deletions
diff --git a/mm/kasan/common.c b/mm/kasan/common.c index eedc3e0fe365..b18189ef3a92 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -345,7 +345,7 @@ static bool ____kasan_slab_free(struct kmem_cache *cache, void *object, if (unlikely(cache->flags & SLAB_TYPESAFE_BY_RCU)) return false; - if (kasan_check_invalid_free(tagged_object)) { + if (!kasan_byte_accessible(tagged_object)) { kasan_report_invalid_free(tagged_object, ip); return true; } @@ -490,3 +490,12 @@ void __kasan_kfree_large(void *ptr, unsigned long ip) kasan_report_invalid_free(ptr, ip); /* The object will be poisoned by kasan_free_pages(). */ } + +bool __kasan_check_byte(const void *address, unsigned long ip) +{ + if (!kasan_byte_accessible(address)) { + kasan_report((unsigned long)address, 1, false, ip); + return false; + } + return true; +} diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c index acab8862dc67..3f17a1218055 100644 --- a/mm/kasan/generic.c +++ b/mm/kasan/generic.c @@ -185,11 +185,11 @@ bool kasan_check_range(unsigned long addr, size_t size, bool write, return check_region_inline(addr, size, write, ret_ip); } -bool kasan_check_invalid_free(void *addr) +bool kasan_byte_accessible(const void *addr) { s8 shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(addr)); - return shadow_byte < 0 || shadow_byte >= KASAN_GRANULE_SIZE; + return shadow_byte >= 0 && shadow_byte < KASAN_GRANULE_SIZE; } void kasan_cache_shrink(struct kmem_cache *cache) diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index 1298b79f9518..cc14b6e6c14c 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -341,20 +341,20 @@ static inline void kasan_unpoison(const void *address, size_t size) round_up(size, KASAN_GRANULE_SIZE), get_tag(address)); } -static inline bool kasan_check_invalid_free(void *addr) +static inline bool kasan_byte_accessible(const void *addr) { u8 ptr_tag = get_tag(addr); - u8 mem_tag = hw_get_mem_tag(addr); + u8 mem_tag = hw_get_mem_tag((void *)addr); - return (mem_tag == KASAN_TAG_INVALID) || - (ptr_tag != KASAN_TAG_KERNEL && ptr_tag != mem_tag); + return (mem_tag != KASAN_TAG_INVALID) && + (ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag); } #else /* CONFIG_KASAN_HW_TAGS */ void kasan_poison(const void *address, size_t size, u8 value); void kasan_unpoison(const void *address, size_t size); -bool kasan_check_invalid_free(void *addr); +bool kasan_byte_accessible(const void *addr); #endif /* CONFIG_KASAN_HW_TAGS */ diff --git a/mm/kasan/sw_tags.c b/mm/kasan/sw_tags.c index cc271fceb5d5..94c2d33be333 100644 --- a/mm/kasan/sw_tags.c +++ b/mm/kasan/sw_tags.c @@ -118,13 +118,13 @@ bool kasan_check_range(unsigned long addr, size_t size, bool write, return true; } -bool kasan_check_invalid_free(void *addr) +bool kasan_byte_accessible(const void *addr) { u8 tag = get_tag(addr); u8 shadow_byte = READ_ONCE(*(u8 *)kasan_mem_to_shadow(kasan_reset_tag(addr))); - return (shadow_byte == KASAN_TAG_INVALID) || - (tag != KASAN_TAG_KERNEL && tag != shadow_byte); + return (shadow_byte != KASAN_TAG_INVALID) && + (tag == KASAN_TAG_KERNEL || tag == shadow_byte); } #define DEFINE_HWASAN_LOAD_STORE(size) \ |