From: Eli Cooper <elicooper@gmx.com>
Date: Thu, 1 Dec 2016 02:05:10 +0000 (+0800)
Subject: ipv4: Set skb->protocol properly for local output
X-Git-Tag: v3.10.105~43
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=85801b799e121eefd31eb8a6bc2eb4064220e687;p=thirdparty%2Fkernel%2Fstable.git

ipv4: Set skb->protocol properly for local output

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: Willy Tarreau <w@1wt.eu>
---

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 57e7450863026..5f077efad29d0 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -97,6 +97,9 @@ int __ip_local_out(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, skb, NULL,
 		       skb_dst(skb)->dev, dst_output);
 }