[PATCH 3.13.y-ckt 92/96] rtnetlink: release net refcnt on error in do_setlink()

[Kamal Mostafa]

3.13.11-ckt13 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Nicolas Dichtel <nicolas.dichtel at 6wind.com>

[ Upstream commit e0ebde0e131b529fd721b24f62872def5ec3718c ]

rtnl_link_get_net() holds a reference on the 'struct net', we need to release
it in case of error.

CC: Eric W. Biederman <ebiederm at xmission.com>
Fixes: b51642f6d77b ("net: Enable a userns root rtnl calls that are safe for unprivilged users")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel at 6wind.com>
Reviewed-by: "Eric W. Biederman" <ebiederm at xmission.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/core/rtnetlink.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 8463178..7dca4b4 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1391,6 +1391,7 @@ static int do_setlink(const struct sk_buff *skb,
 			goto errout;
 		}
 		if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) {
+			put_net(net);
 			err = -EPERM;
 			goto errout;
 		}
-- 
1.9.1