Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b0832a29 authored by Eric Biederman's avatar Eric Biederman Committed by David S. Miller
Browse files

macvlan: Support creating macvlans from macvlans 



When running in a network namespace whose only link to
the outside world is a macvlan device, not being
able to create another macvlan is a real pain.

So modify macvlan creation to allow automatically forward
a creation of a macvlan on a macvlan to become a creation
of a macvlan on the underlying network device.

Signed-off-by: default avatarEric Biederman <ebiederm@aristanetworks.com>
Acked-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f7efb6cc

drivers/net/macvlan.c

+6 −5
Original line number Diff line number Diff line
@@ -461,12 +461,13 @@ static int macvlan_newlink(struct net_device *dev, 
	if (lowerdev == NULL)

		return -ENODEV;



	/* Don't allow macvlans on top of other macvlans - its not really

	 * wrong, but lockdep can't handle it and its not useful for anything

	 * you couldn't do directly on top of the real device.

	/* When creating macvlans on top of other macvlans - use

	 * the real device as the lowerdev.

	 */

	if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops)

		return -ENODEV;

	if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {

		struct macvlan_dev *lowervlan = netdev_priv(lowerdev);

		lowerdev = lowervlan->lowerdev;

	}



	if (!tb[IFLA_MTU])

		dev->mtu = lowerdev->mtu;