Commit cfddd4c3 authored Dec 18, 2017 by Xin Long Committed by David S. Miller Dec 19, 2017

ip_gre: remove the incorrect mtu limit for ipgre tap



ipgre tap driver calls ether_setup(), after commit 61e84623
("net: centralize net_device min/max MTU checking"), the range
of mtu is [min_mtu, max_mtu], which is [68, 1500] by default.

It causes the dev mtu of the ipgre tap device to not be greater
than 1500, this limit value is not correct for ipgre tap device.

Besides, it's .change_mtu already does the right check. So this
patch is just to set max_mtu as 0, and leave the check to it's
.change_mtu.

Fixes: 61e84623 ("net: centralize net_device min/max MTU checking")
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent a93bf0ff

net/ipv4/ip_gre.c

+1 −0

Original line number	Original line	Diff line number	Diff line
	@@ -1310,6 +1310,7 @@ static const struct net_device_ops erspan_netdev_ops = {
	static void ipgre_tap_setup(struct net_device *dev)		static void ipgre_tap_setup(struct net_device *dev)
	{		{
	ether_setup(dev);		ether_setup(dev);
			dev->max_mtu = 0;
	dev->netdev_ops = &gre_tap_netdev_ops;		dev->netdev_ops = &gre_tap_netdev_ops;
	dev->priv_flags &= ~IFF_TX_SKB_SHARING;		dev->priv_flags &= ~IFF_TX_SKB_SHARING;
	dev->priv_flags \|= IFF_LIVE_ADDR_CHANGE;		dev->priv_flags \|= IFF_LIVE_ADDR_CHANGE;

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