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

    net: fix a race in dst_release()

to the 3.10-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:
     net-fix-a-race-in-dst_release.patch
and it can be found in the queue-3.10 subdirectory.

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


>From foo@baz Sat Dec  5 21:18:34 PST 2015
From: Eric Dumazet <[email protected]>
Date: Mon, 9 Nov 2015 17:51:23 -0800
Subject: net: fix a race in dst_release()

From: Eric Dumazet <[email protected]>

[ Upstream commit d69bbf88c8d0b367cf3e3a052f6daadf630ee566 ]

Only cpu seeing dst refcount going to 0 can safely
dereference dst->flags.

Otherwise an other cpu might already have freed the dst.

Fixes: 27b75c95f10d ("net: avoid RCU for NOCACHE dst")
Reported-by: Greg Thelen <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 net/core/dst.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -283,7 +283,7 @@ void dst_release(struct dst_entry *dst)
 
                newrefcnt = atomic_dec_return(&dst->__refcnt);
                WARN_ON(newrefcnt < 0);
-               if (unlikely(dst->flags & DST_NOCACHE) && !newrefcnt)
+               if (!newrefcnt && unlikely(dst->flags & DST_NOCACHE))
                        call_rcu(&dst->rcu_head, dst_destroy_rcu);
        }
 }


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

queue-3.10/ipmr-fix-possible-race-resulting-from-improper-usage-of-ip_inc_stats_bh-in-preemptible-context.patch
queue-3.10/net-avoid-null-deref-in-inet_ctl_sock_destroy.patch
queue-3.10/net-fix-a-race-in-dst_release.patch
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