net: vxlan: properly cleanup devs on module unload

We should use vxlan_dellink() handler in vxlan_exit_net(), since
i) we're not in fast-path and we should be consistent in dismantle
just as we would remove a device through rtnl ops, and more
importantly, ii) in case future code will kfree() memory in
vxlan_dellink(), we would leak it right here unnoticed. Therefore,
do not only half of the cleanup work, but make it properly.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/vxlan.c

@@ -2710,13 +2710,13 @@ static __net_init int vxlan_init_net(struct net *net)
 static __net_exit void vxlan_exit_net(struct net *net)
 {
 	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
-	struct vxlan_dev *vxlan;
-	LIST_HEAD(list);
+	struct vxlan_dev *vxlan, *next;
+	LIST_HEAD(list_kill);
 
 	rtnl_lock();
-	list_for_each_entry(vxlan, &vn->vxlan_list, next)
-		unregister_netdevice_queue(vxlan->dev, &list);
-	unregister_netdevice_many(&list);
+	list_for_each_entry_safe(vxlan, next, &vn->vxlan_list, next)
+		vxlan_dellink(vxlan->dev, &list_kill);
+	unregister_netdevice_many(&list_kill);
 	rtnl_unlock();
 }