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kasan-introduce-kasan_init_cache_meta.patch removed from -mm tree

merged mm-stable Andrew Morton 1 participant 1 message Oct 3, 2022

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The quilt patch titled
Subject: kasan: introduce kasan_init_cache_meta
has been removed from the -mm tree. Its filename was
kasan-introduce-kasan_init_cache_meta.patch

This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Andrey Konovalov <[email protected]>
Subject: kasan: introduce kasan_init_cache_meta
Date: Mon, 5 Sep 2022 23:05:27 +0200

Add a kasan_init_cache_meta() helper that initializes metadata-related cache parameters and use this helper in the common KASAN code.

Put the implementation of this new helper into generic.c, as only the Generic mode uses per-object metadata.

---

 mm/kasan/common.c  |   80 +------------------------------------------
 mm/kasan/generic.c |   79 ++++++++++++++++++++++++++++++++++++++++++
 mm/kasan/kasan.h   |    2 +
 3 files changed, 83 insertions(+), 78 deletions(-)
mm/kasan/common.c renamed from mm/kasan/common.c~kasan-introduce-kasan_init_cache_meta +2 -78
@@ -118,28 +118,9 @@ void __kasan_poison_pages(struct page *p
 			     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_ca
 	 */
 	*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)
mm/kasan/generic.c renamed from mm/kasan/generic.c~kasan-introduce-kasan_init_cache_meta +79 -0

85 lines not on this page · raw message

mm/kasan/kasan.h renamed from mm/kasan/kasan.h~kasan-introduce-kasan_init_cache_meta +2 -0
@@ -297,12 +297,14 @@ struct page *kasan_addr_to_page(const vo
 struct slab *kasan_addr_to_slab(const void *addr);
 
 #ifdef CONFIG_KASAN_GENERIC
+void kasan_init_cache_meta(struct kmem_cache *cache, unsigned int *size);
 void kasan_init_object_meta(struct kmem_cache *cache, const void *object);
 struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
 						const void *object);
 struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
 						const void *object);
 #else
+static inline void kasan_init_cache_meta(struct kmem_cache *cache, unsigned int *size) { }
 static inline void kasan_init_object_meta(struct kmem_cache *cache, const void *object) { }
 #endif
 

_

Patches currently in -mm which might be from [email protected] are

kasan-fix-array-bounds-warnings-in-tests.patch