Patch "ip6_tunnel: Clear IP6CB in ip6tunnel_xmit()" has been added to the 4.8-stable tree

Patch "ip6_tunnel: Clear IP6CB in ip6tunnel_xmit()" has been added to the 4.8-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    ip6_tunnel: Clear IP6CB in ip6tunnel_xmit()

to the 4.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     ip6_tunnel-clear-ip6cb-in-ip6tunnel_xmit.patch
and it can be found in the queue-4.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Fri Nov 18 11:35:46 CET 2016
From: Eli Cooper <elicooper@gmx.com>
Date: Tue, 1 Nov 2016 23:45:12 +0800
Subject: ip6_tunnel: Clear IP6CB in ip6tunnel_xmit()

From: Eli Cooper <elicooper@gmx.com>


[ Upstream commit 23f4ffedb7d751c7e298732ba91ca75d224bc1a6 ]

skb->cb may contain data from previous layers. In the observed scenario,
the garbage data were misinterpreted as IP6CB(skb)->frag_max_size, so
that small packets sent through the tunnel are mistakenly fragmented.

This patch unconditionally clears the control buffer in ip6tunnel_xmit(),
which affects ip6_tunnel, ip6_udp_tunnel and ip6_gre. Currently none of
these tunnels set IP6CB(skb)->flags, otherwise it needs to be done earlier.

Cc: stable@vger.kernel.org
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>
---
 include/net/ip6_tunnel.h |    1 +
 1 file changed, 1 insertion(+)

--- a/include/net/ip6_tunnel.h
+++ b/include/net/ip6_tunnel.h
@@ -145,6 +145,7 @@ static inline void ip6tunnel_xmit(struct
 {
 	int pkt_len, err;
 
+	memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 	pkt_len = skb->len - skb_inner_network_offset(skb);
 	err = ip6_local_out(dev_net(skb_dst(skb)->dev), sk, skb);
 	if (unlikely(net_xmit_eval(err)))


Patches currently in stable-queue which might be from elicooper@gmx.com are

queue-4.8/ip6_tunnel-clear-ip6cb-in-ip6tunnel_xmit.patch