4.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Julien Gomes <julien@xxxxxxxxxx> [ Upstream commit 5c25f65fd1e42685f7ccd80e0621829c105785d9 ] If the name argument of dev_get_valid_name() contains "%d", it will try to assign it a unit number in __dev__alloc_name() and return either the unit number (>= 0) or an error code (< 0). Considering positive values as error values prevent tun device creations relying this mechanism, therefor we should only consider negative values as errors here. Signed-off-by: Julien Gomes <julien@xxxxxxxxxx> Acked-by: Cong Wang <xiyou.wangcong@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/tun.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1814,7 +1814,7 @@ static int tun_set_iff(struct net *net, if (!dev) return -ENOMEM; err = dev_get_valid_name(net, dev, name); - if (err) + if (err < 0) goto err_free_dev; dev_net_set(dev, net);