1 files changed, 35 insertions, 10 deletions

diff --git a/mm/slab_common.c b/mm/slab_common.c
index 9c11e8a937d2..81732d05e74a 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -406,8 +406,9 @@ out_free_cache:
 	goto out;
 }
 
-/*
- * kmem_cache_create_usercopy - Create a cache.
+/**
+ * kmem_cache_create_usercopy - Create a cache with a region suitable
+ * for copying to userspace
  * @name: A string which is used in /proc/slabinfo to identify this cache.
  * @size: The size of objects to be created in this cache.
  * @align: The required alignment for the objects.
@@ -416,7 +417,6 @@ out_free_cache:
  * @usersize: Usercopy region size
  * @ctor: A constructor for the objects.
  *
- * Returns a ptr to the cache on success, NULL on failure.
  * Cannot be called within a interrupt, but can be interrupted.
  * The @ctor is run when new pages are allocated by the cache.
  *
@@ -425,12 +425,14 @@ out_free_cache:
  * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
  * to catch references to uninitialised memory.
  *
- * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check
+ * %SLAB_RED_ZONE - Insert `Red` zones around the allocated memory to check
  * for buffer overruns.
  *
  * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
  * cacheline.  This can be beneficial if you're counting cycles as closely
  * as davem.
+ *
+ * Return: a pointer to the cache on success, NULL on failure.
  */
 struct kmem_cache *
 kmem_cache_create_usercopy(const char *name,
@@ -514,6 +516,31 @@ out_unlock:
 }
 EXPORT_SYMBOL(kmem_cache_create_usercopy);
 
+/**
+ * kmem_cache_create - Create a cache.
+ * @name: A string which is used in /proc/slabinfo to identify this cache.
+ * @size: The size of objects to be created in this cache.
+ * @align: The required alignment for the objects.
+ * @flags: SLAB flags
+ * @ctor: A constructor for the objects.
+ *
+ * Cannot be called within a interrupt, but can be interrupted.
+ * The @ctor is run when new pages are allocated by the cache.
+ *
+ * The flags are
+ *
+ * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
+ * to catch references to uninitialised memory.
+ *
+ * %SLAB_RED_ZONE - Insert `Red` zones around the allocated memory to check
+ * for buffer overruns.
+ *
+ * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
+ * cacheline.  This can be beneficial if you're counting cycles as closely
+ * as davem.
+ *
+ * Return: a pointer to the cache on success, NULL on failure.
+ */
 struct kmem_cache *
 kmem_cache_create(const char *name, unsigned int size, unsigned int align,
 		slab_flags_t flags, void (*ctor)(void *))
@@ -1029,10 +1056,8 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
 
 		index = size_index[size_index_elem(size)];
 	} else {
-		if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) {
-			WARN_ON(1);
+		if (WARN_ON_ONCE(size > KMALLOC_MAX_CACHE_SIZE))
 			return NULL;
-		}
 		index = fls(size - 1);
 	}
 
@@ -1204,7 +1229,7 @@ void *kmalloc_order(size_t size, gfp_t flags, unsigned int order)
 	page = alloc_pages(flags, order);
 	ret = page ? page_address(page) : NULL;
 	kmemleak_alloc(ret, size, 1, flags);
-	kasan_kmalloc_large(ret, size, flags);
+	ret = kasan_kmalloc_large(ret, size, flags);
 	return ret;
 }
 EXPORT_SYMBOL(kmalloc_order);
@@ -1482,7 +1507,7 @@ static __always_inline void *__do_krealloc(const void *p, size_t new_size,
 		ks = ksize(p);
 
 	if (ks >= new_size) {
-		kasan_krealloc((void *)p, new_size, flags);
+		p = kasan_krealloc((void *)p, new_size, flags);
 		return (void *)p;
 	}
 
@@ -1534,7 +1559,7 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags)
 	}
 
 	ret = __do_krealloc(p, new_size, flags);
-	if (ret && p != ret)
+	if (ret && kasan_reset_tag(p) != kasan_reset_tag(ret))
 		kfree(p);
 
 	return ret;