tun: honor IFF_UP in tun_get_user()

If a tun interface is turned down, we should not allow packet injection
into the kernel.

Kernel does not send packets to the tun already.

TUNATTACHFILTER can not be used as only tun_net_xmit() is taking care
of it.

Reported-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2015-12-16 08:57:37 -08:00 committed by David S. Miller
parent 715f504b11
commit 1bd4978a88
1 changed files with 3 additions and 0 deletions

View File

@ -1095,6 +1095,9 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
u32 rxhash;
ssize_t n;
if (!(tun->dev->flags & IFF_UP))
return -EIO;
if (!(tun->flags & IFF_NO_PI)) {
if (len < sizeof(pi))
return -EINVAL;