ipv4: Set skb->protocol properly for local output

BugLink: http://bugs.launchpad.net/bugs/1650607
commit f4180439109aa720774baafdd798b3234ab1a0d2 upstream.

When xfrm is applied to TSO/GSO packets, it follows this path:

    xfrm_output() -> xfrm_output_gso() -> skb_gso_segment()

where skb_gso_segment() relies on skb->protocol to function properly.

This patch sets skb->protocol to ETH_P_IP before dst_output() is called,
fixing a bug where GSO packets sent through a sit tunnel are dropped
when xfrm is involved.

Signed-off-by: Eli Cooper <elicooper@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index f2ad5216c438006e5f62a862913895bd04f2126a..2b7283303650ae9a833582e38908c3a1dca9dae0 100644 (file)
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -102,6 +102,9 @@ int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb)
 
        iph->tot_len = htons(skb->len);
        ip_send_check(iph);
+
+       skb->protocol = htons(ETH_P_IP);
+
        return nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT,
                       net, sk, skb, NULL, skb_dst(skb)->dev,
                       dst_output);