bonding: fix a potential double-unregister
authorCong Wang <xiyou.wangcong@gmail.com>
Sat, 15 Aug 2020 03:05:58 +0000 (20:05 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 26 Aug 2020 09:49:11 +0000 (11:49 +0200)
commit39560b31450bbe023aa09f4049ba02598803516a
tree6e538dcadb025dd3f609317f500e515b279ca924
parentdfdc8eaf69a63ed5af9f67c7d3d1a58fcc71ade1
bonding: fix a potential double-unregister

[ Upstream commit 832707021666411d04795c564a4adea5d6b94f17 ]

When we tear down a network namespace, we unregister all
the netdevices within it. So we may queue a slave device
and a bonding device together in the same unregister queue.

If the only slave device is non-ethernet, it would
automatically unregister the bonding device as well. Thus,
we may end up unregistering the bonding device twice.

Workaround this special case by checking reg_state.

Fixes: 9b5e383c11b0 ("net: Introduce unregister_netdevice_many()")
Reported-by: syzbot+af23e7f3e0a7e10c8b67@syzkaller.appspotmail.com
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/net/bonding/bond_main.c