diff --git a/sys/kern/uipc_domain.c b/sys/kern/uipc_domain.c
--- a/sys/kern/uipc_domain.c
+++ b/sys/kern/uipc_domain.c
@@ -97,6 +97,12 @@
 	return (EOPNOTSUPP);
 }
 
+static int
+pr_ctloutput_notsupp(struct socket *so, struct sockopt *sopt)
+{
+	return (ENOPROTOOPT);
+}
+
 static int
 pr_disconnect_notsupp(struct socket *so)
 {
@@ -194,6 +200,7 @@
 	NOTSUPP(pr_connect2);
 	NOTSUPP(pr_connectat);
 	NOTSUPP(pr_control);
+	NOTSUPP(pr_ctloutput);
 	NOTSUPP(pr_disconnect);
 	NOTSUPP(pr_listen);
 	NOTSUPP(pr_peeraddr);
diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -3804,10 +3804,7 @@
 	CURVNET_SET(so->so_vnet);
 	error = 0;
 	if (sopt->sopt_level != SOL_SOCKET) {
-		if (so->so_proto->pr_ctloutput != NULL)
-			error = (*so->so_proto->pr_ctloutput)(so, sopt);
-		else
-			error = ENOPROTOOPT;
+		error = (*so->so_proto->pr_ctloutput)(so, sopt);
 	} else {
 		switch (sopt->sopt_name) {
 		case SO_ACCEPTFILTER:
@@ -4017,7 +4014,7 @@
 				error = ENOPROTOOPT;
 			break;
 		}
-		if (error == 0 && so->so_proto->pr_ctloutput != NULL)
+		if (error == 0)
 			(void)(*so->so_proto->pr_ctloutput)(so, sopt);
 	}
 bad:
@@ -4068,10 +4065,7 @@
 	CURVNET_SET(so->so_vnet);
 	error = 0;
 	if (sopt->sopt_level != SOL_SOCKET) {
-		if (so->so_proto->pr_ctloutput != NULL)
-			error = (*so->so_proto->pr_ctloutput)(so, sopt);
-		else
-			error = ENOPROTOOPT;
+		error = (*so->so_proto->pr_ctloutput)(so, sopt);
 		CURVNET_RESTORE();
 		return (error);
 	} else {