Patch "ipv6: tcp: add rcu locking in tcp_v6_send_synack()" has been added to the 4.1-stable tree

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

ipv6: tcp: add rcu locking in tcp_v6_send_synack()

to the 4.1-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-tcp-add-rcu-locking-in-tcp_v6_send_synack.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Eric Dumazet <[email protected]>
Date: Fri, 8 Jan 2016 09:35:51 -0800
Subject: ipv6: tcp: add rcu locking in tcp_v6_send_synack()

From: Eric Dumazet <[email protected]>

[ Upstream commit 3e4006f0b86a5ae5eb0e8215f9a9e1db24506977 ]

When first SYNACK is sent, we already hold rcu_read_lock(), but this is not true if a SYNACK is retransmitted, as a timer (soft) interrupt does not hold rcu_read_lock()

---
 net/ipv6/tcp_ipv6.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -465,8 +465,10 @@ static int tcp_v6_send_synack(struct soc
 			fl6->flowlabel = ip6_flowlabel(ipv6_hdr(ireq->pktopts));
 
 		skb_set_queue_mapping(skb, queue_mapping);
+		rcu_read_lock();
 		err = ip6_xmit(sk, skb, fl6, rcu_dereference(np->opt),
 			       np->tclass);
+		rcu_read_unlock();
 		err = net_xmit_eval(err);
 	}
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.1/net-sched-fix-missing-free-per-cpu-on-qstats.patch queue-4.1/ipv6-tcp-add-rcu-locking-in-tcp_v6_send_synack.patch queue-4.1/ipv6-update-skb-csum-when-ce-mark-is-propagated.patch queue-4.1/tcp-dccp-fix-old-style-declarations.patch queue-4.1/net-possible-use-after-free-in-dst_release.patch queue-4.1/phonet-properly-unshare-skbs-in-phonet_rcv.patch queue-4.1/tcp-dccp-fix-timewait-races-in-timer-handling.patch queue-4.1/tcp_yeah-don-t-set-ssthresh-below-2.patch