This is a note to let you know that I've just added the patch titled
bonding: fix a potential double-unregister
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bonding-fix-a-potential-double-unregister.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Wed Aug 26 04:19:14 PM CEST 2020
From: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Date: Fri, 14 Aug 2020 20:05:58 -0700
Subject: bonding: fix a potential double-unregister
From: Cong Wang <xiyou.wangcong@xxxxxxxxx>
[ 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@xxxxxxxxxxxxxxxxxxxxxxxxx
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Cc: Andy Gospodarek <andy@xxxxxxxxxxxxx>
Cc: Jay Vosburgh <j.vosburgh@xxxxxxxxx>
Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/bonding/bond_main.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1940,7 +1940,8 @@ static int bond_release_and_destroy(str
int ret;
ret = bond_release(bond_dev, slave_dev);
- 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 %s\n",
bond_dev->name);
Patches currently in stable-queue which might be from xiyou.wangcong@xxxxxxxxx are
queue-4.4/tipc-fix-uninit-skb-data-in-tipc_nl_compat_dumpit.patch
queue-4.4/bonding-fix-a-potential-double-unregister.patch
