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-rw-r--r--drivers/net/macvlan.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 2e4bcd5654c4..e8dc2f44fec9 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -384,6 +384,13 @@ 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.
+ */
+ if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops)
+ return -ENODEV;
+
if (!tb[IFLA_MTU])
dev->mtu = lowerdev->mtu;
else if (dev->mtu > lowerdev->mtu)