Commit 1bd4978a authored Dec 16, 2015 by Eric Dumazet Committed by David S. Miller Dec 17, 2015

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>

parent 715f504b

drivers/net/tun.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -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;