From afbb64f1d85b7d8c2938031c3567946b5d10da4f Mon Sep 17 00:00:00 2001
From: "Alexander V. Chernikov" <melifaro@FreeBSD.org>
Date: Sun, 11 Apr 2021 17:47:03 +0100
Subject: [PATCH] Fix vlan creation for the older ifconfig(8) binaries.

Reported by:	allanjude
MFC after:	immediately
---
 sys/net/if_vlan.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/sys/net/if_vlan.c b/sys/net/if_vlan.c
index 229cd331c7a1..bd3a5335a97f 100644
--- a/sys/net/if_vlan.c
+++ b/sys/net/if_vlan.c
@@ -1015,6 +1015,10 @@ vlan_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
 		vid = vlr.vlr_tag;
 		proto = vlr.vlr_proto;
 
+#ifdef COMPAT_FREEBSD12
+		if (proto == 0)
+			proto = ETHERTYPE_VLAN;
+#endif
 		p = ifunit_ref(vlr.vlr_parent);
 		if (p == NULL)
 			return (ENXIO);
@@ -1947,6 +1951,10 @@ vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
 			error = ENOENT;
 			break;
 		}
+#ifdef COMPAT_FREEBSD12
+		if (vlr.vlr_proto == 0)
+			vlr.vlr_proto = ETHERTYPE_VLAN;
+#endif
 		oldmtu = ifp->if_mtu;
 		error = vlan_config(ifv, p, vlr.vlr_tag, vlr.vlr_proto);
 		if_rele(p);