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

    ipv6: stop sending PTB packets for MTU < 1280

to the 3.14-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:
     ipv6-stop-sending-ptb-packets-for-mtu-1280.patch
and it can be found in the queue-3.14 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 Thu Feb 12 09:26:08 HKT 2015
From: Hagen Paul Pfeifer <ha...@jauu.net>
Date: Thu, 15 Jan 2015 22:34:25 +0100
Subject: ipv6: stop sending PTB packets for MTU < 1280

From: Hagen Paul Pfeifer <ha...@jauu.net>

[ Upstream commit 9d289715eb5c252ae15bd547cb252ca547a3c4f2 ]

Reduce the attack vector and stop generating IPv6 Fragment Header for
paths with an MTU smaller than the minimum required IPv6 MTU
size (1280 byte) - called atomic fragments.

See IETF I-D "Deprecating the Generation of IPv6 Atomic Fragments" [1]
for more information and how this "feature" can be misused.

[1] https://tools.ietf.org/html/draft-ietf-6man-deprecate-atomfrag-generation-00

Signed-off-by: Fernando Gont <fg...@si6networks.com>
Signed-off-by: Hagen Paul Pfeifer <ha...@jauu.net>
Acked-by: Hannes Frederic Sowa <han...@stressinduktion.org>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 net/ipv6/route.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1160,12 +1160,9 @@ static void ip6_rt_update_pmtu(struct ds
                struct net *net = dev_net(dst->dev);
 
                rt6->rt6i_flags |= RTF_MODIFIED;
-               if (mtu < IPV6_MIN_MTU) {
-                       u32 features = dst_metric(dst, RTAX_FEATURES);
+               if (mtu < IPV6_MIN_MTU)
                        mtu = IPV6_MIN_MTU;
-                       features |= RTAX_FEATURE_ALLFRAG;
-                       dst_metric_set(dst, RTAX_FEATURES, features);
-               }
+
                dst_metric_set(dst, RTAX_MTU, mtu);
                rt6_update_expires(rt6, net->ipv6.sysctl.ip6_rt_mtu_expires);
        }


Patches currently in stable-queue which might be from ha...@jauu.net are

queue-3.14/ipv6-stop-sending-ptb-packets-for-mtu-1280.patch
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