static int
ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
{
- if (new_mtu < IPV6_MIN_MTU) {
- return -EINVAL;
+ struct ip6_tnl *tnl = netdev_priv(dev);
+
+ if (tnl->parms.proto == IPPROTO_IPIP) {
+ if (new_mtu < 68)
+ return -EINVAL;
+ } else {
+ if (new_mtu < IPV6_MIN_MTU)
+ return -EINVAL;
}
+ if (new_mtu > 0xFFF8 - dev->hard_header_len)
+ return -EINVAL;
dev->mtu = new_mtu;
return 0;
}