[3.16.y-ckt stable] Patch "netfilter: nfnetlink: don't probe module if it exists" has been added to staging queue

[Luis Henriques]

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

    netfilter: nfnetlink: don't probe module if it exists

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-ckt21.

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 a0b88a28f372f0e0352b98dab4d2d20fc17e01d9 Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw at strlen.de>
Date: Tue, 27 Oct 2015 13:20:25 +0100
Subject: netfilter: nfnetlink: don't probe module if it exists

commit dbc3617f4c1f9fcbe63612048cb9583fea1e11ab upstream.

nfnetlink_bind request_module()s all the time as nfnetlink_get_subsys()
shifts the argument by 8 to obtain the subsys id.

So using type instead of type << 8 always returns NULL.

Fixes: 03292745b02d11 ("netlink: add nlk->netlink_bind hook for module auto-loading")
Signed-off-by: Florian Westphal <fw at strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo at netfilter.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/netfilter/nfnetlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index 6ae88ace21cb..cddab2101569 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -406,7 +406,7 @@ static int nfnetlink_bind(int group)
 	int type = nfnl_group2type[group];

 	rcu_read_lock();
-	ss = nfnetlink_get_subsys(type);
+	ss = nfnetlink_get_subsys(type << 8);
 	rcu_read_unlock();
 	if (!ss)
 		request_module("nfnetlink-subsys-%d", type);