1 files changed, 45 insertions, 1 deletions

diff --git a/mm/slub.c b/mm/slub.c
index 850737bdfbd8..9adae58462f8 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3629,6 +3629,7 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
  */
 static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
 {
+	LIST_HEAD(discard);
 	struct page *page, *h;
 
 	BUG_ON(irqs_disabled());
@@ -3636,13 +3637,16 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
 	list_for_each_entry_safe(page, h, &n->partial, lru) {
 		if (!page->inuse) {
 			remove_partial(n, page);
-			discard_slab(s, page);
+			list_add(&page->lru, &discard);
 		} else {
 			list_slab_objects(s, page,
 			"Objects remaining in %s on __kmem_cache_shutdown()");
 		}
 	}
 	spin_unlock_irq(&n->list_lock);
+
+	list_for_each_entry_safe(page, h, &discard, lru)
+		discard_slab(s, page);
 }
 
 /*
@@ -3764,6 +3768,46 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node)
 EXPORT_SYMBOL(__kmalloc_node);
 #endif
 
+#ifdef CONFIG_HARDENED_USERCOPY
+/*
+ * Rejects objects that are incorrectly sized.
+ *
+ * Returns NULL if check passes, otherwise const char * to name of cache
+ * to indicate an error.
+ */
+const char *__check_heap_object(const void *ptr, unsigned long n,
+				struct page *page)
+{
+	struct kmem_cache *s;
+	unsigned long offset;
+	size_t object_size;
+
+	/* Find object and usable object size. */
+	s = page->slab_cache;
+	object_size = slab_ksize(s);
+
+	/* Reject impossible pointers. */
+	if (ptr < page_address(page))
+		return s->name;
+
+	/* Find offset within object. */
+	offset = (ptr - page_address(page)) % s->size;
+
+	/* Adjust for redzone and reject if within the redzone. */
+	if (kmem_cache_debug(s) && s->flags & SLAB_RED_ZONE) {
+		if (offset < s->red_left_pad)
+			return s->name;
+		offset -= s->red_left_pad;
+	}
+
+	/* Allow address range falling entirely within object size. */
+	if (offset <= object_size && n <= object_size - offset)
+		return NULL;
+
+	return s->name;
+}
+#endif /* CONFIG_HARDENED_USERCOPY */
+
 static size_t __ksize(const void *object)
 {
 	struct page *page;