macvlan: forbid L2 fowarding offload for macvtap

L2 fowarding offload will bypass the rx handler of real device. This will make the packet could not be forwarded to macvtap device. Another problem is the dev_hard_start_xmit() called for macvtap does not have any synchronization. Fix this by forbidding L2 forwarding for macvtap. Cc: John Fastabend <[email protected]> Cc: Neil Horman <[email protected]> Acked-by: Neil Horman <[email protected]> Signed-off-by: Jason Wang <[email protected]> Acked-by: John Fastabend <[email protected]> Signed-off-by: David S. Miller <[email protected]>
torvalds · Jan 10, 2014 · b13ba1b · b13ba1b
1 parent c4d7099
commit b13ba1b
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
@@ -338,6 +338,8 @@ static const struct header_ops macvlan_hard_header_ops = {
 	.cache_update	= eth_header_cache_update,
 };
 
+static struct rtnl_link_ops macvlan_link_ops;
+
 static int macvlan_open(struct net_device *dev)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
@@ -353,7 +355,8 @@ static int macvlan_open(struct net_device *dev)
 		goto hash_add;
 	}
 
-	if (lowerdev->features & NETIF_F_HW_L2FW_DOFFLOAD) {
+	if (lowerdev->features & NETIF_F_HW_L2FW_DOFFLOAD &&
+	    dev->rtnl_link_ops == &macvlan_link_ops) {
 		vlan->fwd_priv =
 		      lowerdev->netdev_ops->ndo_dfwd_add_station(lowerdev, dev);