diff options
Diffstat (limited to 'mm/kasan')
| -rw-r--r-- | mm/kasan/Makefile | 3 | ||||
| -rw-r--r-- | mm/kasan/kasan.c | 63 | ||||
| -rw-r--r-- | mm/kasan/kasan.h | 3 | ||||
| -rw-r--r-- | mm/kasan/report.c | 8 |
4 files changed, 37 insertions, 40 deletions
diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile index 1548749a3d45..2976a9ee104f 100644 --- a/mm/kasan/Makefile +++ b/mm/kasan/Makefile @@ -7,5 +7,4 @@ CFLAGS_REMOVE_kasan.o = -pg # see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63533 CFLAGS_kasan.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -obj-y := kasan.o report.o kasan_init.o -obj-$(CONFIG_SLAB) += quarantine.o +obj-y := kasan.o report.o kasan_init.o quarantine.o diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index 6845f9294696..b6f99e81bfeb 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -351,7 +351,6 @@ void kasan_free_pages(struct page *page, unsigned int order) KASAN_FREE_PAGE); } -#ifdef CONFIG_SLAB /* * Adaptive redzone policy taken from the userspace AddressSanitizer runtime. * For larger allocations larger redzones are used. @@ -373,16 +372,8 @@ void kasan_cache_create(struct kmem_cache *cache, size_t *size, unsigned long *flags) { int redzone_adjust; - /* Make sure the adjusted size is still less than - * KMALLOC_MAX_CACHE_SIZE. - * TODO: this check is only useful for SLAB, but not SLUB. We'll need - * to skip it for SLUB when it starts using kasan_cache_create(). - */ - if (*size > KMALLOC_MAX_CACHE_SIZE - - sizeof(struct kasan_alloc_meta) - - sizeof(struct kasan_free_meta)) - return; - *flags |= SLAB_KASAN; + int orig_size = *size; + /* Add alloc meta. */ cache->kasan_info.alloc_meta_offset = *size; *size += sizeof(struct kasan_alloc_meta); @@ -395,14 +386,26 @@ void kasan_cache_create(struct kmem_cache *cache, size_t *size, } redzone_adjust = optimal_redzone(cache->object_size) - (*size - cache->object_size); + if (redzone_adjust > 0) *size += redzone_adjust; - *size = min(KMALLOC_MAX_CACHE_SIZE, - max(*size, - cache->object_size + - optimal_redzone(cache->object_size))); + + *size = min(KMALLOC_MAX_SIZE, max(*size, cache->object_size + + optimal_redzone(cache->object_size))); + + /* + * If the metadata doesn't fit, don't enable KASAN at all. + */ + if (*size <= cache->kasan_info.alloc_meta_offset || + *size <= cache->kasan_info.free_meta_offset) { + cache->kasan_info.alloc_meta_offset = 0; + cache->kasan_info.free_meta_offset = 0; + *size = orig_size; + return; + } + + *flags |= SLAB_KASAN; } -#endif void kasan_cache_shrink(struct kmem_cache *cache) { @@ -414,6 +417,14 @@ void kasan_cache_destroy(struct kmem_cache *cache) quarantine_remove_cache(cache); } +size_t kasan_metadata_size(struct kmem_cache *cache) +{ + return (cache->kasan_info.alloc_meta_offset ? + sizeof(struct kasan_alloc_meta) : 0) + + (cache->kasan_info.free_meta_offset ? + sizeof(struct kasan_free_meta) : 0); +} + void kasan_poison_slab(struct page *page) { kasan_poison_shadow(page_address(page), @@ -431,16 +442,13 @@ void kasan_poison_object_data(struct kmem_cache *cache, void *object) kasan_poison_shadow(object, round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE), KASAN_KMALLOC_REDZONE); -#ifdef CONFIG_SLAB if (cache->flags & SLAB_KASAN) { struct kasan_alloc_meta *alloc_info = get_alloc_info(cache, object); alloc_info->state = KASAN_STATE_INIT; } -#endif } -#ifdef CONFIG_SLAB static inline int in_irqentry_text(unsigned long ptr) { return (ptr >= (unsigned long)&__irqentry_text_start && @@ -501,7 +509,6 @@ struct kasan_free_meta *get_free_info(struct kmem_cache *cache, BUILD_BUG_ON(sizeof(struct kasan_free_meta) > 32); return (void *)object + cache->kasan_info.free_meta_offset; } -#endif void kasan_slab_alloc(struct kmem_cache *cache, void *object, gfp_t flags) { @@ -522,16 +529,16 @@ static void kasan_poison_slab_free(struct kmem_cache *cache, void *object) bool kasan_slab_free(struct kmem_cache *cache, void *object) { -#ifdef CONFIG_SLAB /* RCU slabs could be legally used after free within the RCU period */ if (unlikely(cache->flags & SLAB_DESTROY_BY_RCU)) return false; if (likely(cache->flags & SLAB_KASAN)) { - struct kasan_alloc_meta *alloc_info = - get_alloc_info(cache, object); - struct kasan_free_meta *free_info = - get_free_info(cache, object); + struct kasan_alloc_meta *alloc_info; + struct kasan_free_meta *free_info; + + alloc_info = get_alloc_info(cache, object); + free_info = get_free_info(cache, object); switch (alloc_info->state) { case KASAN_STATE_ALLOC: @@ -550,10 +557,6 @@ bool kasan_slab_free(struct kmem_cache *cache, void *object) } } return false; -#else - kasan_poison_slab_free(cache, object); - return false; -#endif } void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size, @@ -576,7 +579,6 @@ void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size, kasan_unpoison_shadow(object, size); kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start, KASAN_KMALLOC_REDZONE); -#ifdef CONFIG_SLAB if (cache->flags & SLAB_KASAN) { struct kasan_alloc_meta *alloc_info = get_alloc_info(cache, object); @@ -585,7 +587,6 @@ void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size, alloc_info->alloc_size = size; set_track(&alloc_info->track, flags); } -#endif } EXPORT_SYMBOL(kasan_kmalloc); diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index fb87923552ef..31972cdba433 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -95,7 +95,6 @@ struct kasan_alloc_meta *get_alloc_info(struct kmem_cache *cache, struct kasan_free_meta *get_free_info(struct kmem_cache *cache, const void *object); - static inline const void *kasan_shadow_to_mem(const void *shadow_addr) { return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET) @@ -110,7 +109,7 @@ static inline bool kasan_report_enabled(void) void kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip); -#ifdef CONFIG_SLAB +#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB) void quarantine_put(struct kasan_free_meta *info, struct kmem_cache *cache); void quarantine_reduce(void); void quarantine_remove_cache(struct kmem_cache *cache); diff --git a/mm/kasan/report.c b/mm/kasan/report.c index b3c122ddd454..861b9776841a 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -116,7 +116,6 @@ static inline bool init_task_stack_addr(const void *addr) sizeof(init_thread_union.stack)); } -#ifdef CONFIG_SLAB static void print_track(struct kasan_track *track) { pr_err("PID = %u\n", track->pid); @@ -130,8 +129,8 @@ static void print_track(struct kasan_track *track) } } -static void object_err(struct kmem_cache *cache, struct page *page, - void *object, char *unused_reason) +static void kasan_object_err(struct kmem_cache *cache, struct page *page, + void *object, char *unused_reason) { struct kasan_alloc_meta *alloc_info = get_alloc_info(cache, object); struct kasan_free_meta *free_info; @@ -162,7 +161,6 @@ static void object_err(struct kmem_cache *cache, struct page *page, break; } } -#endif static void print_address_description(struct kasan_access_info *info) { @@ -177,7 +175,7 @@ static void print_address_description(struct kasan_access_info *info) struct kmem_cache *cache = page->slab_cache; object = nearest_obj(cache, page, (void *)info->access_addr); - object_err(cache, page, object, + kasan_object_err(cache, page, object, "kasan: bad access detected"); return; } |