diff options
Diffstat (limited to 'mm/kasan/generic.c')
| -rw-r--r-- | mm/kasan/generic.c | 47 |
1 files changed, 17 insertions, 30 deletions
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c index 1900f8576034..d54e89f8c3e7 100644 --- a/mm/kasan/generic.c +++ b/mm/kasan/generic.c @@ -334,14 +334,6 @@ DEFINE_ASAN_SET_SHADOW(f3); DEFINE_ASAN_SET_SHADOW(f5); DEFINE_ASAN_SET_SHADOW(f8); -/* Only allow cache merging when no per-object metadata is present. */ -slab_flags_t kasan_never_merge(void) -{ - if (!kasan_requires_meta()) - return 0; - return SLAB_KASAN; -} - /* * Adaptive redzone policy taken from the userspace AddressSanitizer runtime. * For larger allocations larger redzones are used. @@ -370,15 +362,13 @@ void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, return; /* - * SLAB_KASAN is used to mark caches that are sanitized by KASAN - * and that thus have per-object metadata. - * Currently this flag is used in two places: - * 1. In slab_ksize() to account for per-object metadata when - * calculating the size of the accessible memory within the object. - * 2. In slab_common.c via kasan_never_merge() to prevent merging of - * caches with per-object metadata. + * SLAB_KASAN is used to mark caches that are sanitized by KASAN and + * that thus have per-object metadata. Currently, this flag is used in + * slab_ksize() to account for per-object metadata when calculating the + * size of the accessible memory within the object. Additionally, we use + * SLAB_NO_MERGE to prevent merging of caches with per-object metadata. */ - *flags |= SLAB_KASAN; + *flags |= SLAB_KASAN | SLAB_NO_MERGE; ok_size = *size; @@ -402,9 +392,12 @@ void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, * 1. Object is SLAB_TYPESAFE_BY_RCU, which means that it can * be touched after it was freed, or * 2. Object has a constructor, which means it's expected to - * retain its content until the next allocation. + * retain its content until the next allocation, or + * 3. It is from a kmalloc cache which enables the debug option + * to store original size. */ - if ((cache->flags & SLAB_TYPESAFE_BY_RCU) || cache->ctor) { + if ((cache->flags & SLAB_TYPESAFE_BY_RCU) || cache->ctor || + slub_debug_orig_size(cache)) { cache->kasan_info.free_meta_offset = *size; *size += sizeof(struct kasan_free_meta); goto free_meta_added; @@ -531,7 +524,11 @@ size_t kasan_metadata_size(struct kmem_cache *cache, bool in_object) sizeof(struct kasan_free_meta) : 0); } -static void __kasan_record_aux_stack(void *addr, depot_flags_t depot_flags) +/* + * This function avoids dynamic memory allocations and thus can be called from + * contexts that do not allow allocating memory. + */ +void kasan_record_aux_stack(void *addr) { struct slab *slab = kasan_addr_to_slab(addr); struct kmem_cache *cache; @@ -548,17 +545,7 @@ static void __kasan_record_aux_stack(void *addr, depot_flags_t depot_flags) return; alloc_meta->aux_stack[1] = alloc_meta->aux_stack[0]; - alloc_meta->aux_stack[0] = kasan_save_stack(0, depot_flags); -} - -void kasan_record_aux_stack(void *addr) -{ - return __kasan_record_aux_stack(addr, STACK_DEPOT_FLAG_CAN_ALLOC); -} - -void kasan_record_aux_stack_noalloc(void *addr) -{ - return __kasan_record_aux_stack(addr, 0); + alloc_meta->aux_stack[0] = kasan_save_stack(0, 0); } void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags) |