diff --git a/drivers/net/dummy.c b/drivers/net/dummy.c
index e31ab3b94c6f385389095d9740d95826e2690db7..58483af80bdb99bcced68e8938338e7dc5514f6a 100644
--- a/drivers/net/dummy.c
+++ b/drivers/net/dummy.c
@@ -353,7 +353,7 @@ static void dummy_setup(struct net_device *dev)
 	eth_hw_addr_random(dev);
 
 	dev->min_mtu = 0;
-	dev->max_mtu = ETH_MAX_MTU;
+	dev->max_mtu = 0;
 }
 
 static int dummy_validate(struct nlattr *tb[], struct nlattr *data[],
diff --git a/drivers/net/ifb.c b/drivers/net/ifb.c
index 8870bd2a2e8a2439c4a0618506375db6b9b4f653..0008da7e9d4cc5f3d716803dd8855bd1a341f516 100644
--- a/drivers/net/ifb.c
+++ b/drivers/net/ifb.c
@@ -231,6 +231,9 @@ static void ifb_setup(struct net_device *dev)
 	eth_hw_addr_random(dev);
 	dev->needs_free_netdev = true;
 	dev->priv_destructor = ifb_dev_free;
+
+	dev->min_mtu = 0;
+	dev->max_mtu = 0;
 }
 
 static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev)