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" <davem@davemloft.net>
CC: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
CC: James Morris <jmorris@namei.org>
CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 5719d6ba0824b377aef689f4e0e1c425fc8df910..12a92e3349ed5ab322496b553abf944acd9f1d4c 100644 (file)
--- 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) {

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 6a66adba0c229a0fd11c5806163a4cb87eb9483c..3a70567846aaab8be248493b92ec1e8da3655eca 100644 (file)
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1634,7 +1634,7 @@ int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
        struct ip6_tnl *tnl = netdev_priv(dev);
 
        if (tnl->parms.proto == IPPROTO_IPIP) {
-               if (new_mtu < 68)
+               if (new_mtu < ETH_MIN_MTU)
                        return -EINVAL;
        } else {
                if (new_mtu < IPV6_MIN_MTU)
@@ -1787,6 +1787,8 @@ ip6_tnl_dev_init_gen(struct net_device *dev)
        dev->mtu = ETH_DATA_LEN - t_hlen;
        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;
 
        return 0;
 

diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 8a02ca8a11af4b388bfe996711458efd46b641cf..35c5b2d8c401a99f1344c50ddd3956c4e6f6a53e 100644 (file)
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -812,30 +812,11 @@ vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
        return err;
 }
 
-/**
- * vti6_tnl_change_mtu - change mtu manually for tunnel device
- *   @dev: virtual device associated with tunnel
- *   @new_mtu: the new mtu
- *
- * Return:
- *   0 on success,
- *   %-EINVAL if mtu too small
- **/
-static int vti6_change_mtu(struct net_device *dev, int new_mtu)
-{
-       if (new_mtu < IPV6_MIN_MTU)
-               return -EINVAL;
-
-       dev->mtu = new_mtu;
-       return 0;
-}
-
 static const struct net_device_ops vti6_netdev_ops = {
        .ndo_init       = vti6_dev_init,
        .ndo_uninit     = vti6_dev_uninit,
        .ndo_start_xmit = vti6_tnl_xmit,
        .ndo_do_ioctl   = vti6_ioctl,
-       .ndo_change_mtu = vti6_change_mtu,
        .ndo_get_stats64 = ip_tunnel_get_stats64,
        .ndo_get_iflink = ip6_tnl_get_iflink,
 };
@@ -855,6 +836,8 @@ static void vti6_dev_setup(struct net_device *dev)
        dev->type = ARPHRD_TUNNEL6;
        dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr);
        dev->mtu = ETH_DATA_LEN;
+       dev->min_mtu = IPV6_MIN_MTU;
+       dev->max_mtu = IP_MAX_MTU;
        dev->flags |= IFF_NOARP;
        dev->addr_len = sizeof(struct in6_addr);
        netif_keep_dst(dev);

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index b1cdf8009d29c4a36a9c7f3f545930134b0d51d5..dc7a3449ffc1c1eceaf2c2e6e6acff4423d6d1d5 100644 (file)
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -1318,23 +1318,11 @@ done:
        return err;
 }
 
-static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
-{
-       struct ip_tunnel *tunnel = netdev_priv(dev);
-       int t_hlen = tunnel->hlen + sizeof(struct iphdr);
-
-       if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - t_hlen)
-               return -EINVAL;
-       dev->mtu = new_mtu;
-       return 0;
-}
-
 static const struct net_device_ops ipip6_netdev_ops = {
        .ndo_init       = ipip6_tunnel_init,
        .ndo_uninit     = ipip6_tunnel_uninit,
        .ndo_start_xmit = sit_tunnel_xmit,
        .ndo_do_ioctl   = ipip6_tunnel_ioctl,
-       .ndo_change_mtu = ipip6_tunnel_change_mtu,
        .ndo_get_stats64 = ip_tunnel_get_stats64,
        .ndo_get_iflink = ip_tunnel_get_iflink,
 };
@@ -1365,6 +1353,8 @@ static void ipip6_tunnel_setup(struct net_device *dev)
        dev->type               = ARPHRD_SIT;
        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->flags              = IFF_NOARP;
        netif_keep_dst(dev);
        dev->addr_len           = 4;