ip6_tunnel: remove magic mtu value 0xFFF8

I don't know where this value comes from (probably a copy and paste and
paste and paste ...).
Let's use standard values which are a bit greater.

Link: https://git.kernel.org/pub/scm/linux/kernel/git/davem/netdev-vger-cvs.git/commit/?id=e5afd356a411a
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Nicolas Dichtel 2018-05-31 10:59:33 +02:00 committed by David S. Miller
parent 82612de1c9
commit f7ff1fde94
2 changed files with 11 additions and 5 deletions

View File

@ -1692,8 +1692,13 @@ int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
if (new_mtu < ETH_MIN_MTU)
return -EINVAL;
}
if (new_mtu > 0xFFF8 - dev->hard_header_len)
if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) {
if (new_mtu > IP6_MAX_MTU - dev->hard_header_len)
return -EINVAL;
} else {
if (new_mtu > IP_MAX_MTU - dev->hard_header_len)
return -EINVAL;
}
dev->mtu = new_mtu;
return 0;
}
@ -1841,7 +1846,7 @@ ip6_tnl_dev_init_gen(struct net_device *dev)
if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
dev->mtu -= 8;
dev->min_mtu = ETH_MIN_MTU;
dev->max_mtu = 0xFFF8 - dev->hard_header_len;
dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len;
return 0;

View File

@ -1371,7 +1371,7 @@ static void ipip6_tunnel_setup(struct net_device *dev)
dev->hard_header_len = LL_MAX_HEADER + t_hlen;
dev->mtu = ETH_DATA_LEN - t_hlen;
dev->min_mtu = IPV6_MIN_MTU;
dev->max_mtu = 0xFFF8 - t_hlen;
dev->max_mtu = IP6_MAX_MTU - t_hlen;
dev->flags = IFF_NOARP;
netif_keep_dst(dev);
dev->addr_len = 4;
@ -1583,7 +1583,8 @@ static int ipip6_newlink(struct net *src_net, struct net_device *dev,
if (tb[IFLA_MTU]) {
u32 mtu = nla_get_u32(tb[IFLA_MTU]);
if (mtu >= IPV6_MIN_MTU && mtu <= 0xFFF8 - dev->hard_header_len)
if (mtu >= IPV6_MIN_MTU &&
mtu <= IP6_MAX_MTU - dev->hard_header_len)
dev->mtu = mtu;
}