From b96f9afee4eb5229c80afa3d97ccf725fb1b89a6 Mon Sep 17 00:00:00 2001 From: Jarod Wilson Date: Thu, 20 Oct 2016 13:55:24 -0400 Subject: ipv4/6: use core net MTU range checking ipv4/ip_tunnel: - min_mtu = 68, max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen - preserve all ndo_change_mtu checks for now to prevent regressions ipv6/ip6_tunnel: - min_mtu = 68, max_mtu = 0xFFF8 - dev->hard_header_len - preserve all ndo_change_mtu checks for now to prevent regressions ipv6/ip6_vti: - min_mtu = 1280, max_mtu = 65535 - remove redundant vti6_change_mtu ipv6/sit: - min_mtu = 1280, max_mtu = 0xFFF8 - t_hlen - remove redundant ipip6_tunnel_change_mtu CC: netdev@vger.kernel.org CC: "David S. Miller" CC: Alexey Kuznetsov CC: James Morris CC: Hideaki YOSHIFUJI CC: Patrick McHardy Signed-off-by: Jarod Wilson Signed-off-by: David S. Miller --- net/ipv4/ip_tunnel.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'net/ipv4/ip_tunnel.c') diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 5719d6ba0824..12a92e3349ed 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -358,6 +358,7 @@ static struct ip_tunnel *ip_tunnel_create(struct net *net, { struct ip_tunnel *nt; struct net_device *dev; + int t_hlen; BUG_ON(!itn->fb_tunnel_dev); dev = __ip_tunnel_create(net, itn->fb_tunnel_dev->rtnl_link_ops, parms); @@ -367,6 +368,9 @@ static struct ip_tunnel *ip_tunnel_create(struct net *net, dev->mtu = ip_tunnel_bind_dev(dev); nt = netdev_priv(dev); + t_hlen = nt->hlen + sizeof(struct iphdr); + dev->min_mtu = ETH_MIN_MTU; + dev->max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen; ip_tunnel_add(itn, nt); return nt; } @@ -929,7 +933,7 @@ int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict) int t_hlen = tunnel->hlen + sizeof(struct iphdr); int max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen; - if (new_mtu < 68) + if (new_mtu < ETH_MIN_MTU) return -EINVAL; if (new_mtu > max_mtu) { -- cgit v1.2.3-55-g7522