From 832707021666411d04795c564a4adea5d6b94f17 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Fri, 14 Aug 2020 20:05:58 -0700 Subject: bonding: fix a potential double-unregister 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 Cc: Andy Gospodarek Cc: Jay Vosburgh Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 4239cdcfd798..415a37e44cae 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -2207,7 +2207,8 @@ static int bond_release_and_destroy(struct net_device *bond_dev, int ret; ret = __bond_release_one(bond_dev, slave_dev, false, true); - if (ret == 0 && !bond_has_slaves(bond)) { + if (ret == 0 && !bond_has_slaves(bond) && + bond_dev->reg_state != NETREG_UNREGISTERING) { bond_dev->priv_flags |= IFF_DISABLE_NETPOLL; netdev_info(bond_dev, "Destroying bond\n"); bond_remove_proc_entry(bond); -- cgit v1.2.3