[PATCH 3.13 061/212] ip_tunnel: Initialize the fallback device properly

[Kamal Mostafa]

3.13.11.4 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Steffen Klassert <steffen.klassert at secunet.com>

[ Upstream commit 78ff4be45a4c51d8fb21ad92e4fabb467c6c3eeb ]

We need to initialize the fallback device to have a correct mtu
set on this device. Otherwise the mtu is set to null and the device
is unusable.

Fixes: fd58156e456d ("IPIP: Use ip-tunneling code.")
Cc: Pravin B Shelar <pshelar at nicira.com>
Signed-off-by: Steffen Klassert <steffen.klassert at secunet.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/ipv4/ip_tunnel.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 30a6000..a39c5cf 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -855,6 +855,7 @@ int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
 	 */
 	if (!IS_ERR(itn->fb_tunnel_dev)) {
 		itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
+		itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
 		ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
 	}
 	rtnl_unlock();
-- 
1.9.1