Patch "ipv6: sctp: fix lockdep splat in sctp_v6_get_dst()" has been added to the 3.18-stable tree

Patch "ipv6: sctp: fix lockdep splat in sctp_v6_get_dst()" has been added to the 3.18-stable tree

[gregkh]

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

    ipv6: sctp: fix lockdep splat in sctp_v6_get_dst()

to the 3.18-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-sctp-fix-lockdep-splat-in-sctp_v6_get_dst.patch
and it can be found in the queue-3.18 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 69ce6487dcd364245a3d26322fc8f4ffd1e8d947 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Mon, 7 Dec 2015 08:25:21 -0800
Subject: ipv6: sctp: fix lockdep splat in sctp_v6_get_dst()

From: Eric Dumazet <edumazet@google.com>

commit 69ce6487dcd364245a3d26322fc8f4ffd1e8d947 upstream.

While cooking the sctp np->opt rcu fixes, I forgot to move
one rcu_read_unlock() after the added rcu_dereference() in
sctp_v6_get_dst()

This gave lockdep warnings reported by Dave Jones.

Fixes: c836a8ba9386 ("ipv6: sctp: add rcu protection around np->opt")
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/sctp/ipv6.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -323,14 +323,13 @@ static void sctp_v6_get_dst(struct sctp_
 			}
 		}
 	}
-	rcu_read_unlock();
-
 	if (baddr) {
 		fl6->saddr = baddr->v6.sin6_addr;
 		fl6->fl6_sport = baddr->v6.sin6_port;
 		final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
 		dst = ip6_dst_lookup_flow(sk, fl6, final_p);
 	}
+	rcu_read_unlock();
 
 out:
 	if (!IS_ERR_OR_NULL(dst)) {


Patches currently in stable-queue which might be from edumazet@google.com are

queue-3.18/ipv6-sctp-add-rcu-protection-around-np-opt.patch
queue-3.18/ipv6-sctp-fix-lockdep-splat-in-sctp_v6_get_dst.patch