tipc: add net device to skb before UDP xmit

Prior to this patch enabling a IPv4 UDP bearer caused a null pointer
dereference in iptunnel_xmit_stats(), when it tried to dereference the
net device from the skb. To resolve this we now point the skb device
to the net device resolved from the routing table.

Fixes: 039f50629b7f (ip_tunnel: Move stats update to iptunnel_xmit())
Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index d63a911e7fe2..f22a5bb169c9 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -181,6 +181,8 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
                         err = PTR_ERR(rt);
                         goto tx_error;
                 }
+
+                skb->dev = rt->dst.dev;
                 ttl = ip4_dst_hoplimit(&rt->dst);
                 udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
                                     dst->ipv4.s_addr, 0, ttl, 0, src->udp_port,