linux-kernel - [PATCH 046/118] bonding: fix bonding_masters race condition in bond unloading

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue,  7 May 2013 14:38:12 +0100
From:	Luis Henriques <luis.henriques@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	Nikolay Aleksandrov <nikolay@...hat.com>,
	"David S. Miller" <davem@...emloft.net>,
	Luis Henriques <luis.henriques@...onical.com>
Subject: [PATCH 046/118] bonding: fix bonding_masters race condition in bond unloading

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

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

From: "nikolay@...hat.com" <nikolay@...hat.com>

commit 69b0216ac255f523556fa3d4ff030d857eaaa37f upstream.

While the bonding module is unloading, it is considered that after
rtnl_link_unregister all bond devices are destroyed but since no
synchronization mechanism exists, a new bond device can be created
via bonding_masters before unregister_pernet_subsys which would
lead to multiple problems (e.g. NULL pointer dereference, wrong RIP,
list corruption).

This patch fixes the issue by removing any bond devices left in the
netns after bonding_masters is removed from sysfs.

Signed-off-by: Nikolay Aleksandrov <nikolay@...hat.com>
Acked-by: Veaceslav Falico <vfalico@...hat.com>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Luis Henriques <luis.henriques@...onical.com>
---
 drivers/net/bonding/bond_main.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 1a6b118..5fc31a1 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4870,9 +4870,18 @@ static int __net_init bond_net_init(struct net *net)
 static void __net_exit bond_net_exit(struct net *net)
 {
 	struct bond_net *bn = net_generic(net, bond_net_id);
+	struct bonding *bond, *tmp_bond;
+	LIST_HEAD(list);
 
 	bond_destroy_sysfs(bn);
 	bond_destroy_proc_dir(bn);
+
+	/* Kill off any bonds created after unregistering bond rtnl ops */
+	rtnl_lock();
+	list_for_each_entry_safe(bond, tmp_bond, &bn->dev_list, bond_list)
+		unregister_netdevice_queue(bond->dev, &list);
+	unregister_netdevice_many(&list);
+	rtnl_unlock();
 }
 
 static struct pernet_operations bond_net_ops = {
-- 
1.8.1.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/