diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 65a8e5c..3c461e1 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -464,7 +464,8 @@
 	upcall->dp_ifindex = dp_ifindex;
 
 	nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_KEY);
-	ovs_nla_put_flow(upcall_info->key, upcall_info->key, user_skb);
+	err = ovs_nla_put_flow(upcall_info->key, upcall_info->key, user_skb);
+	BUG_ON(err);
 	nla_nest_end(user_skb, nla);
 
 	if (upcall_info->userdata)