From 26d31ac11fa47a0ee8dc4c64136ea34feda57e3e Mon Sep 17 00:00:00 2001 From: David Ahern Date: Wed, 26 Apr 2017 07:58:22 -0700 Subject: [PATCH] net: vrf: Do not allow looback to be moved to a VRF Moving the loopback into a VRF breaks networking for the default VRF. Since the VRF device is the loopback for VRF domains, there is no reason to move the loopback. Given the repercussions, block attempts to set lo into a VRF. Signed-off-by: David Ahern Reviewed-by: Greg Rose Signed-off-by: David S. Miller --- drivers/net/vrf.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index aa5d30428bba..ceda5861da78 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -877,6 +877,12 @@ static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev) { int ret; + /* do not allow loopback device to be enslaved to a VRF. + * The vrf device acts as the loopback for the vrf. + */ + if (port_dev == dev_net(dev)->loopback_dev) + return -EOPNOTSUPP; + port_dev->priv_flags |= IFF_L3MDEV_SLAVE; ret = netdev_master_upper_dev_link(port_dev, dev, NULL, NULL); if (ret < 0) -- GitLab