1 files changed, 49 insertions, 8 deletions

diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c
index 38f1dd79acdb..8df666bb23be 100644
--- a/mm/kasan/kasan.c
+++ b/mm/kasan/kasan.c
@@ -388,6 +388,16 @@ void kasan_cache_create(struct kmem_cache *cache, size_t *size,
 }
 #endif
 
+void kasan_cache_shrink(struct kmem_cache *cache)
+{
+	quarantine_remove_cache(cache);
+}
+
+void kasan_cache_destroy(struct kmem_cache *cache)
+{
+	quarantine_remove_cache(cache);
+}
+
 void kasan_poison_slab(struct page *page)
 {
 	kasan_poison_shadow(page_address(page),
@@ -482,7 +492,7 @@ void kasan_slab_alloc(struct kmem_cache *cache, void *object, gfp_t flags)
 	kasan_kmalloc(cache, object, cache->object_size, flags);
 }
 
-void kasan_slab_free(struct kmem_cache *cache, void *object)
+void kasan_poison_slab_free(struct kmem_cache *cache, void *object)
 {
 	unsigned long size = cache->object_size;
 	unsigned long rounded_up_size = round_up(size, KASAN_SHADOW_SCALE_SIZE);
@@ -491,18 +501,43 @@ void kasan_slab_free(struct kmem_cache *cache, void *object)
 	if (unlikely(cache->flags & SLAB_DESTROY_BY_RCU))
 		return;
 
+	kasan_poison_shadow(object, rounded_up_size, KASAN_KMALLOC_FREE);
+}
+
+bool kasan_slab_free(struct kmem_cache *cache, void *object)
+{
 #ifdef CONFIG_SLAB
-	if (cache->flags & SLAB_KASAN) {
-		struct kasan_free_meta *free_info =
-			get_free_info(cache, object);
+	/* 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);
-		alloc_info->state = KASAN_STATE_FREE;
-		set_track(&free_info->track, GFP_NOWAIT);
+		struct kasan_free_meta *free_info =
+			get_free_info(cache, object);
+
+		switch (alloc_info->state) {
+		case KASAN_STATE_ALLOC:
+			alloc_info->state = KASAN_STATE_QUARANTINE;
+			quarantine_put(free_info, cache);
+			set_track(&free_info->track, GFP_NOWAIT);
+			kasan_poison_slab_free(cache, object);
+			return true;
+		case KASAN_STATE_QUARANTINE:
+		case KASAN_STATE_FREE:
+			pr_err("Double free");
+			dump_stack();
+			break;
+		default:
+			break;
+		}
 	}
+	return false;
+#else
+	kasan_poison_slab_free(cache, object);
+	return false;
 #endif
-
-	kasan_poison_shadow(object, rounded_up_size, KASAN_KMALLOC_FREE);
 }
 
 void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size,
@@ -511,6 +546,9 @@ void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size,
 	unsigned long redzone_start;
 	unsigned long redzone_end;
 
+	if (flags & __GFP_RECLAIM)
+		quarantine_reduce();
+
 	if (unlikely(object == NULL))
 		return;
 
@@ -541,6 +579,9 @@ void kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
 	unsigned long redzone_start;
 	unsigned long redzone_end;
 
+	if (flags & __GFP_RECLAIM)
+		quarantine_reduce();
+
 	if (unlikely(ptr == NULL))
 		return;