4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet <edumazet@xxxxxxxxxx> commit 9180bb4f046064dfa4541488102703b402bb04e1 upstream. In my latest patch I missed one rcu_read_unlock(), in case device is down. Fixes: 4477138fa0ae ("tun: properly test for IFF_UP") Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/tun.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1569,6 +1569,7 @@ drop: rcu_read_lock(); if (unlikely(!(tun->dev->flags & IFF_UP))) { err = -EIO; + rcu_read_unlock(); goto drop; }