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-rw-r--r--mm/kasan/common.c80
1 files changed, 2 insertions, 78 deletions
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index d0300954d76b..b6a74fe5e740 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -118,28 +118,9 @@ void __kasan_poison_pages(struct page *page, unsigned int order, bool init)
KASAN_PAGE_FREE, init);
}
-/*
- * Adaptive redzone policy taken from the userspace AddressSanitizer runtime.
- * For larger allocations larger redzones are used.
- */
-static inline unsigned int optimal_redzone(unsigned int object_size)
-{
- return
- object_size <= 64 - 16 ? 16 :
- object_size <= 128 - 32 ? 32 :
- object_size <= 512 - 64 ? 64 :
- object_size <= 4096 - 128 ? 128 :
- object_size <= (1 << 14) - 256 ? 256 :
- object_size <= (1 << 15) - 512 ? 512 :
- object_size <= (1 << 16) - 1024 ? 1024 : 2048;
-}
-
void __kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
slab_flags_t *flags)
{
- unsigned int ok_size;
- unsigned int optimal_size;
-
/*
* SLAB_KASAN is used to mark caches as ones that are sanitized by
* KASAN. Currently this flag is used in two places:
@@ -149,65 +130,8 @@ void __kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
*/
*flags |= SLAB_KASAN;
- if (!kasan_requires_meta())
- return;
-
- ok_size = *size;
-
- /* Add alloc meta into redzone. */
- cache->kasan_info.alloc_meta_offset = *size;
- *size += sizeof(struct kasan_alloc_meta);
-
- /*
- * If alloc meta doesn't fit, don't add it.
- * This can only happen with SLAB, as it has KMALLOC_MAX_SIZE equal
- * to KMALLOC_MAX_CACHE_SIZE and doesn't fall back to page_alloc for
- * larger sizes.
- */
- if (*size > KMALLOC_MAX_SIZE) {
- cache->kasan_info.alloc_meta_offset = 0;
- *size = ok_size;
- /* Continue, since free meta might still fit. */
- }
-
- /* Only the generic mode uses free meta or flexible redzones. */
- if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
- cache->kasan_info.free_meta_offset = KASAN_NO_FREE_META;
- return;
- }
-
- /*
- * Add free meta into redzone when it's not possible to store
- * it in the object. This is the case when:
- * 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, or
- * 3. Object is too small.
- * Otherwise cache->kasan_info.free_meta_offset = 0 is implied.
- */
- if ((cache->flags & SLAB_TYPESAFE_BY_RCU) || cache->ctor ||
- cache->object_size < sizeof(struct kasan_free_meta)) {
- ok_size = *size;
-
- cache->kasan_info.free_meta_offset = *size;
- *size += sizeof(struct kasan_free_meta);
-
- /* If free meta doesn't fit, don't add it. */
- if (*size > KMALLOC_MAX_SIZE) {
- cache->kasan_info.free_meta_offset = KASAN_NO_FREE_META;
- *size = ok_size;
- }
- }
-
- /* Calculate size with optimal redzone. */
- optimal_size = cache->object_size + optimal_redzone(cache->object_size);
- /* Limit it with KMALLOC_MAX_SIZE (relevant for SLAB only). */
- if (optimal_size > KMALLOC_MAX_SIZE)
- optimal_size = KMALLOC_MAX_SIZE;
- /* Use optimal size if the size with added metas is not large enough. */
- if (*size < optimal_size)
- *size = optimal_size;
+ if (kasan_requires_meta())
+ kasan_init_cache_meta(cache, size);
}
void __kasan_cache_create_kmalloc(struct kmem_cache *cache)