diff --git a/mm/slob.c b/mm/slob.c
index f729c46639fa6606a9591d1f9891a928f801f47d..3d73b3b8fb1dcba18cfde8f088e9c6d974ce4508 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -554,7 +554,7 @@ void *kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node)
 					    flags, node);
 	}
 
-	if (c->ctor)
+	if (b && c->ctor)
 		c->ctor(b);
 
 	kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags);