Patch "vrf: Fix use after free and double free in vrf_finish_output" has been added to the 4.14-stable tree

Patch "vrf: Fix use after free and double free in vrf_finish_output" has been added to the 4.14-stable tree

[gregkh]

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

    vrf: Fix use after free and double free in vrf_finish_output

to the 4.14-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:
     vrf-fix-use-after-free-and-double-free-in-vrf_finish_output.patch
and it can be found in the queue-4.14 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 Tue Apr 10 23:20:08 CEST 2018
From: David Ahern <dsahern@gmail.com>
Date: Thu, 29 Mar 2018 12:49:52 -0700
Subject: vrf: Fix use after free and double free in vrf_finish_output

From: David Ahern <dsahern@gmail.com>


[ Upstream commit 82dd0d2a9a76fc8fa2b18d80b987d455728bf83a ]

Miguel reported an skb use after free / double free in vrf_finish_output
when neigh_output returns an error. The vrf driver should return after
the call to neigh_output as it takes over the skb on error path as well.

Patch is a simplified version of Miguel's patch which was written for 4.9,
and updated to top of tree.

Fixes: 8f58336d3f78a ("net: Add ethernet header for pass through VRF device")
Signed-off-by: Miguel Fadon Perlines <mfadon@teldat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/vrf.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -579,12 +579,13 @@ static int vrf_finish_output(struct net
 	if (!IS_ERR(neigh)) {
 		sock_confirm_neigh(skb, neigh);
 		ret = neigh_output(neigh, skb);
+		rcu_read_unlock_bh();
+		return ret;
 	}
 
 	rcu_read_unlock_bh();
 err:
-	if (unlikely(ret < 0))
-		vrf_tx_error(skb->dev, skb);
+	vrf_tx_error(skb->dev, skb);
 	return ret;
 }
 


Patches currently in stable-queue which might be from dsahern@gmail.com are

queue-4.14/perf-tools-fix-copyfile_offset-update-of-output-offset.patch
queue-4.14/net-ipv6-fix-route-leaking-between-vrfs.patch
queue-4.14/vrf-fix-use-after-free-and-double-free-in-vrf_finish_output.patch