ip6_pol_route panic: Do not allow VLAN on loopback
authorKrishna Kumar <krkumar2@in.ibm.com>
Thu, 14 Apr 2011 06:07:04 +0000 (06:07 +0000)
committerDavid S. Miller <davem@davemloft.net>
Mon, 18 Apr 2011 06:27:16 +0000 (23:27 -0700)
Several tests in the ipv6 routing code check IFF_LOOPBACK, and
allowing stacking such as VLAN'ing on top of loopback results in a
netdevice which reports IFF_LOOPBACK but really isn't the loopback
device.

Instead of spamming the ipv6 routing code with even more special tests,
simply disallow VLAN over loopback.

The result of this patch is:

# modprobe 8021q
# vconfig add lo 43
ERROR: trying to add VLAN #43 to IF -:lo:-  error: Operation not supported

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/loopback.c

index ea0dc451da9c874716c689a051cb967082c8bf6b..d70fb76edb7717062544a3c87d27e5799d0348c9 100644 (file)
@@ -173,7 +173,8 @@ static void loopback_setup(struct net_device *dev)
                | NETIF_F_RXCSUM
                | NETIF_F_HIGHDMA
                | NETIF_F_LLTX
-               | NETIF_F_NETNS_LOCAL;
+               | NETIF_F_NETNS_LOCAL
+               | NETIF_F_VLAN_CHALLENGED;
        dev->ethtool_ops        = &loopback_ethtool_ops;
        dev->header_ops         = &eth_header_ops;
        dev->netdev_ops         = &loopback_ops;