CVE-2026-64043

In the Linux kernel, the following vulnerability has been resolved:

ovpn: fix race between deleting interface and adding new peer

While deleting an existing ovpn interface, there is a very

narrow window where adding a new peer via netlink may cause

the netdevice to hang and prevent its unregistration.

It may happen during ovpn_dellink(), when all existing peers are

freed and the device is queued for deregistration, but a

CMD_PEER_NEW message comes in adding a new peer that takes again

a reference to the netdev.

At this point there is no way to release the device because we are

under the assumption that all peers were already released.

Fix the race condition by releasing all peers in ndo_uninit(),

when the netdevice has already been removed from the netdev

list.

Also ovpn_peer_add() has now an extra check that forces the

function to bail out if the device reg_state is not REGISTERED.

This way any incoming CMD_PEER_NEW racing with the interface

deletion routine will simply stop before adding the peer.

Note that the above check happens while holding the netdev_lock

to prevent racing netdev state changes.

ovpn_dellink() is now empty and can be removed.