@@ -1539,6 +1539,15 @@ static int fl_change(struct net *net, struct sk_buff *in_skb,
/* user specifies a handle and it doesn't exist */
err = idr_alloc_u32(&head->handle_idr, fnew, &handle,
handle, GFP_ATOMIC);
+
+ /* Filter with specified handle was concurrently
+ * inserted after initial check in cls_api. This is not
+ * necessarily an error if NLM_F_EXCL is not set in
+ * message flags. Returning EAGAIN will cause cls_api to
+ * try to update concurrently inserted rule.
+ */
+ if (err == -ENOSPC)
+ err = -EAGAIN;
} else {
handle = 1;
err = idr_alloc_u32(&head->handle_idr, fnew, &handle,