--- a/sys/netgraph/ksocket/ng_ksocket.c
+++ b/sys/netgraph/ksocket/ng_ksocket.c
@@ -486,7 +486,7 @@
 	/* Internal commands */
 	{
 	  NGM_KSOCKET_INTERNAL_COOKIE,
-	  NGM_KSOCKET_INTERNAL_UPCALL,
+	  NULL,		/* NGM_KSOCKET_INTERNAL_UPCALL: not externally invokable */
 	  "upcall",
 	  NULL,
 	  NULL