From e6b6133de54db31efc5b28b52a5892584dba409a Mon Sep 17 00:00:00 2001 From: "nikolay@redhat.com" Date: Sat, 6 Apr 2013 00:54:38 +0000 Subject: [PATCH] bonding: fix bonding_masters race condition in bond unloading [ Upstream commit 69b0216ac255f523556fa3d4ff030d857eaaa37f ] 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 Acked-by: Veaceslav Falico Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- 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 27cdf1f5e604..00299f5a021f 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -4919,9 +4919,18 @@ 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 = { -- 2.39.5