[3.16.y-ckt stable] Patch "net: Reset secmark when scrubbing packet" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    net: Reset secmark when scrubbing packet

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt5.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From a6dd222200202728ca591ea4bbe7ba78caf740ae Mon Sep 17 00:00:00 2001
From: Thomas Graf <tgraf at suug.ch>
Date: Tue, 23 Dec 2014 01:13:18 +0100
Subject: net: Reset secmark when scrubbing packet

commit b8fb4e0648a2ab3734140342002f68fb0c7d1602 upstream.

skb_scrub_packet() is called when a packet switches between a context
such as between underlay and overlay, between namespaces, or between
L3 subnets.

While we already scrub the packet mark, connection tracking entry,
and cached destination, the security mark/context is left intact.

It seems wrong to inherit the security context of a packet when going
from overlay to underlay or across forwarding paths.

Signed-off-by: Thomas Graf <tgraf at suug.ch>
Acked-by: Flavio Leitner <fbl at sysclose.org>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/core/skbuff.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index f5f14d54d6a2..fe07faaed256 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3933,6 +3933,7 @@ void skb_scrub_packet(struct sk_buff *skb, bool xnet)
 	skb->ignore_df = 0;
 	skb_dst_drop(skb);
 	skb->mark = 0;
+	skb_init_secmark(skb);
 	secpath_reset(skb);
 	nf_reset(skb);
 	nf_reset_trace(skb);
--
2.1.4