1 files changed, 33 insertions, 10 deletions

diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index fc732b78daf7..0d5519fcb438 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -162,22 +162,25 @@ static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
 	struct net *net = dev_net(net_dev);
 	struct net_device *parent_dev;
 	struct net *parent_net;
+	int iflink;
 	bool ret;
 
 	/* check if this is a batman-adv mesh interface */
 	if (batadv_softif_is_valid(net_dev))
 		return true;
 
-	/* no more parents..stop recursion */
-	if (dev_get_iflink(net_dev) == 0 ||
-	    dev_get_iflink(net_dev) == net_dev->ifindex)
+	iflink = dev_get_iflink(net_dev);
+	if (iflink == 0)
 		return false;
 
 	parent_net = batadv_getlink_net(net_dev, net);
 
+	/* iflink to itself, most likely physical device */
+	if (net == parent_net && iflink == net_dev->ifindex)
+		return false;
+
 	/* recurse over the parent device */
-	parent_dev = __dev_get_by_index((struct net *)parent_net,
-					dev_get_iflink(net_dev));
+	parent_dev = __dev_get_by_index((struct net *)parent_net, iflink);
 	/* if we got a NULL parent_dev there is something broken.. */
 	if (!parent_dev) {
 		pr_err("Cannot find parent device\n");
@@ -227,14 +230,15 @@ static struct net_device *batadv_get_real_netdevice(struct net_device *netdev)
 	struct net_device *real_netdev = NULL;
 	struct net *real_net;
 	struct net *net;
-	int ifindex;
+	int iflink;
 
 	ASSERT_RTNL();
 
 	if (!netdev)
 		return NULL;
 
-	if (netdev->ifindex == dev_get_iflink(netdev)) {
+	iflink = dev_get_iflink(netdev);
+	if (iflink == 0) {
 		dev_hold(netdev);
 		return netdev;
 	}
@@ -244,9 +248,16 @@ static struct net_device *batadv_get_real_netdevice(struct net_device *netdev)
 		goto out;
 
 	net = dev_net(hard_iface->soft_iface);
-	ifindex = dev_get_iflink(netdev);
 	real_net = batadv_getlink_net(netdev, net);
-	real_netdev = dev_get_by_index(real_net, ifindex);
+
+	/* iflink to itself, most likely physical device */
+	if (net == real_net && netdev->ifindex == iflink) {
+		real_netdev = netdev;
+		dev_hold(real_netdev);
+		goto out;
+	}
+
+	real_netdev = dev_get_by_index(real_net, iflink);
 
 out:
 	if (hard_iface)
@@ -632,7 +643,19 @@ out:
  */
 void batadv_update_min_mtu(struct net_device *soft_iface)
 {
-	soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
+	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
+	int limit_mtu;
+	int mtu;
+
+	mtu = batadv_hardif_min_mtu(soft_iface);
+
+	if (bat_priv->mtu_set_by_user)
+		limit_mtu = bat_priv->mtu_set_by_user;
+	else
+		limit_mtu = ETH_DATA_LEN;
+
+	mtu = min(mtu, limit_mtu);
+	dev_set_mtu(soft_iface, mtu);
 
 	/* Check if the local translate table should be cleaned up to match a
 	 * new (and smaller) MTU.