tun: Fix unregister race
It is possible for tun_chr_close to race with dellink on the
a tun device. In which case if __tun_get runs before dellink
but dellink runs before tun_chr_close calls unregister_netdevice
we will attempt to unregister the netdevice after it is already
gone.
The two cases are already serialized on the rtnl_lock, so I have
gone for the cheap simple fix of moving rtnl_lock to cover __tun_get
in tun_chr_close. Eliminating the possibility of the tun device
being unregistered between __tun_get and unregister_netdevice in
tun_chr_close.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Tested-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed