[3.13.y-ckt stable] Patch "ipv4: fix nexthop attlen check in fib_nh_match" has been added to staging queue

[Kamal Mostafa]

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

    ipv4: fix nexthop attlen check in fib_nh_match

to the linux-3.13.y-queue branch of the 3.13.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-3.13.y-queue

This patch is scheduled to be released in version 3.13.11-ckt13.

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

For more information about the 3.13.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 7604f22eaf3297c1e7f5d0886974c9d8e5fe6136 Mon Sep 17 00:00:00 2001
From: Jiri Pirko <jiri at resnulli.us>
Date: Mon, 13 Oct 2014 16:34:10 +0200
Subject: ipv4: fix nexthop attlen check in fib_nh_match

[ Upstream commit f76936d07c4eeb36d8dbb64ebd30ab46ff85d9f7 ]

fib_nh_match does not match nexthops correctly. Example:

ip route add 172.16.10/24 nexthop via 192.168.122.12 dev eth0 \
                          nexthop via 192.168.122.13 dev eth0
ip route del 172.16.10/24 nexthop via 192.168.122.14 dev eth0 \
                          nexthop via 192.168.122.15 dev eth0

Del command is successful and route is removed. After this patch
applied, the route is correctly matched and result is:
RTNETLINK answers: No such process

Please consider this for stable trees as well.

Fixes: 4e902c57417c4 ("[IPv4]: FIB configuration using struct fib_config")
Signed-off-by: Jiri Pirko <jiri at resnulli.us>
Acked-by: Eric Dumazet <edumazet at google.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/ipv4/fib_semantics.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 8fccc50..1fd7cb2 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -534,7 +534,7 @@ int fib_nh_match(struct fib_config *cfg, struct fib_info *fi)
 			return 1;

 		attrlen = rtnh_attrlen(rtnh);
-		if (attrlen < 0) {
+		if (attrlen > 0) {
 			struct nlattr *nla, *attrs = rtnh_attrs(rtnh);

 			nla = nla_find(attrs, attrlen, RTA_GATEWAY);
--
1.9.1