[3.16.y-ckt stable] Patch "ipvs: do not use random local source address for tunnels" has been added to staging queue

[Luis Henriques]

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

    ipvs: do not use random local source address for tunnels

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/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt17.

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 760967baabae66d596a0c6f7aa822e5bb32f7abd Mon Sep 17 00:00:00 2001
From: Julian Anastasov <ja at ssi.bg>
Date: Sat, 27 Jun 2015 14:39:30 +0300
Subject: ipvs: do not use random local source address for tunnels

commit 4754957f04f5f368792a0eb7dab0ae89fb93dcfd upstream.

Michael Vallaly reports about wrong source address used
in rare cases for tunneled traffic. Looks like
__ip_vs_get_out_rt in 3.10+ is providing uninitialized
dest_dst->dst_saddr.ip because ip_vs_dest_dst_alloc uses
kmalloc. While we retry after seeing EINVAL from routing
for data that does not look like valid local address, it
still succeeded when this memory was previously used from
other dests and with different local addresses. As result,
we can use valid local address that is not suitable for
our real server.

Fix it by providing 0.0.0.0 every time our cache is refreshed.
By this way we will get preferred source address from routing.

Reported-by: Michael Vallaly <lvs at nolatency.com>
Fixes: 026ace060dfe ("ipvs: optimize dst usage for real server")
Signed-off-by: Julian Anastasov <ja at ssi.bg>
Signed-off-by: Simon Horman <horms at verge.net.au>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/netfilter/ipvs/ip_vs_xmit.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c
index 6f70bdd3a90a..180f7624bcd4 100644
--- a/net/netfilter/ipvs/ip_vs_xmit.c
+++ b/net/netfilter/ipvs/ip_vs_xmit.c
@@ -129,7 +129,6 @@ static struct rtable *do_output_route4(struct net *net, __be32 daddr,

 	memset(&fl4, 0, sizeof(fl4));
 	fl4.daddr = daddr;
-	fl4.saddr = (rt_mode & IP_VS_RT_MODE_CONNECT) ? *saddr : 0;
 	fl4.flowi4_flags = (rt_mode & IP_VS_RT_MODE_KNOWN_NH) ?
 			   FLOWI_FLAG_KNOWN_NH : 0;