diff --git a/ofproto/ofproto-dpif-upcall.c b/ofproto/ofproto-dpif-upcall.c
index 7577d14ec..53e59580d 100644
--- a/ofproto/ofproto-dpif-upcall.c
+++ b/ofproto/ofproto-dpif-upcall.c
@@ -1563,8 +1563,11 @@ process_upcall(struct udpif *udpif, struct upcall *upcall,
             memset(&ipfix_actions, 0, sizeof ipfix_actions);
 
             if (upcall->out_tun_key) {
-                odp_tun_key_from_attr(upcall->out_tun_key, &output_tunnel_key,
-                                      NULL);
+                if (odp_tun_key_from_attr(upcall->out_tun_key,
+                                          &output_tunnel_key,
+                                          NULL) != ODP_FIT_ERROR) {
+                    return EINVAL;
+                }
             }
 
             actions_len = dpif_read_actions(udpif, upcall, flow,