Index: kernel/generic/src/mm/malloc.c
===================================================================
--- kernel/generic/src/mm/malloc.c	(revision 23d4e6aeb10c07b0fc1436805639ab2e50cf7514)
+++ kernel/generic/src/mm/malloc.c	(revision 1d93f7790fbe3c17814e579d72eef9a2ef4aa292)
@@ -192,5 +192,5 @@
 	void *obj = mem_alloc(alignof(max_align_t), size + _offset);
 	if (!obj)
-	   return NULL;
+		return NULL;
 
 	obj += _offset;
@@ -209,6 +209,8 @@
 	 * slab_free() will detect it and panic.
 	 */
-	size_t size = ((size_t *) obj)[-1];
-	mem_free(obj - _offset, alignof(max_align_t), size + _offset);
+	if (obj) {
+		size_t size = ((size_t *) obj)[-1];
+		mem_free(obj - _offset, alignof(max_align_t), size + _offset);
+	}
 }