Merge branch 'MTU-core-range-checking-more'

Jarod Wilson says:

====================
net: use core MTU range checking everywhere

This stack of patches should get absolutely everything in the kernel
converted from doing their own MTU range checking to the core MTU range
checking. This second spin includes alterations to hopefully fix all
concerns raised with the first, as well as including some additional
changes to drivers and infrastructure where I completely missed necessary
updates.

These have all been built through the 0-day build infrastructure via the
(rebasing) master branch at https://github.com/jarodwilson/linux-muck, which
at the time of the most recent compile across 147 configs, was based on
net-next at commit 7b1536ef0aa0.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

15 files changed, 32 insertions, 111 deletions

diff --git a/net/802/fddi.c b/net/802/fddi.c
index 7d3a0af954e8..6356623fc238 100644
--- a/net/802/fddi.c
+++ b/net/802/fddi.c
@@ -141,15 +141,6 @@ __be16 fddi_type_trans(struct sk_buff *skb, struct net_device *dev)
 
 EXPORT_SYMBOL(fddi_type_trans);
 
-int fddi_change_mtu(struct net_device *dev, int new_mtu)
-{
-	if ((new_mtu < FDDI_K_SNAP_HLEN) || (new_mtu > FDDI_K_SNAP_DLEN))
-		return -EINVAL;
-	dev->mtu = new_mtu;
-	return 0;
-}
-EXPORT_SYMBOL(fddi_change_mtu);
-
 static const struct header_ops fddi_header_ops = {
 	.create		= fddi_header,
 };
@@ -161,6 +152,8 @@ static void fddi_setup(struct net_device *dev)
 	dev->type		= ARPHRD_FDDI;
 	dev->hard_header_len	= FDDI_K_SNAP_HLEN+3;	/* Assume 802.2 SNAP hdr len + 3 pad bytes */
 	dev->mtu		= FDDI_K_SNAP_DLEN;	/* Assume max payload of 802.2 SNAP frame */
+	dev->min_mtu		= FDDI_K_SNAP_HLEN;
+	dev->max_mtu		= FDDI_K_SNAP_DLEN;
 	dev->addr_len		= FDDI_K_ALEN;
 	dev->tx_queue_len	= 100;			/* Long queues on FDDI */
 	dev->flags		= IFF_BROADCAST | IFF_MULTICAST;
diff --git a/net/802/hippi.c b/net/802/hippi.c
index ade1a52cdcff..5e4427beab2b 100644
--- a/net/802/hippi.c
+++ b/net/802/hippi.c
@@ -116,18 +116,6 @@ __be16 hippi_type_trans(struct sk_buff *skb, struct net_device *dev)
 
 EXPORT_SYMBOL(hippi_type_trans);
 
-int hippi_change_mtu(struct net_device *dev, int new_mtu)
-{
-	/*
-	 * HIPPI's got these nice large MTUs.
-	 */
-	if ((new_mtu < 68) || (new_mtu > 65280))
-		return -EINVAL;
-	dev->mtu = new_mtu;
-	return 0;
-}
-EXPORT_SYMBOL(hippi_change_mtu);
-
 /*
  * For HIPPI we will actually use the lower 4 bytes of the hardware
  * address as the I-FIELD rather than the actual hardware address.
@@ -174,6 +162,8 @@ static void hippi_setup(struct net_device *dev)
 	dev->type		= ARPHRD_HIPPI;
 	dev->hard_header_len 	= HIPPI_HLEN;
 	dev->mtu		= 65280;
+	dev->min_mtu		= 68;
+	dev->max_mtu		= 65280;
 	dev->addr_len		= HIPPI_ALEN;
 	dev->tx_queue_len	= 25 /* 5 */;
 	memset(dev->broadcast, 0xFF, HIPPI_ALEN);
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index fbfacd51aa34..10da6c588bf8 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -826,5 +826,8 @@ void vlan_setup(struct net_device *dev)
 	dev->destructor		= vlan_dev_free;
 	dev->ethtool_ops	= &vlan_ethtool_ops;
 
+	dev->min_mtu		= 0;
+	dev->max_mtu		= ETH_MAX_MTU;
+
 	eth_zero_addr(dev->broadcast);
 }
diff --git a/net/atm/lec.c b/net/atm/lec.c
index 5d2693826afb..779b3fa6052d 100644
--- a/net/atm/lec.c
+++ b/net/atm/lec.c
@@ -544,15 +544,6 @@ send_to_lecd(struct lec_priv *priv, atmlec_msg_type type,
 	return 0;
 }
 
-/* shamelessly stolen from drivers/net/net_init.c */
-static int lec_change_mtu(struct net_device *dev, int new_mtu)
-{
-	if ((new_mtu < 68) || (new_mtu > 18190))
-		return -EINVAL;
-	dev->mtu = new_mtu;
-	return 0;
-}
-
 static void lec_set_multicast_list(struct net_device *dev)
 {
 	/*
@@ -565,7 +556,6 @@ static const struct net_device_ops lec_netdev_ops = {
 	.ndo_open		= lec_open,
 	.ndo_stop		= lec_close,
 	.ndo_start_xmit		= lec_start_xmit,
-	.ndo_change_mtu		= lec_change_mtu,
 	.ndo_tx_timeout		= lec_tx_timeout,
 	.ndo_set_rx_mode	= lec_set_multicast_list,
 };
@@ -742,6 +732,7 @@ static int lecd_attach(struct atm_vcc *vcc, int arg)
 		if (!dev_lec[i])
 			return -ENOMEM;
 		dev_lec[i]->netdev_ops = &lec_netdev_ops;
+		dev_lec[i]->max_mtu = 18190;
 		snprintf(dev_lec[i]->name, IFNAMSIZ, "lec%d", i);
 		if (register_netdev(dev_lec[i])) {
 			free_netdev(dev_lec[i]);
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 49e16b6e0ba3..112679d64be5 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -158,17 +158,6 @@ static int batadv_interface_set_mac_addr(struct net_device *dev, void *p)
 	return 0;
 }
 
-static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu)
-{
-	/* check ranges */
-	if ((new_mtu < 68) || (new_mtu > batadv_hardif_min_mtu(dev)))
-		return -EINVAL;
-
-	dev->mtu = new_mtu;
-
-	return 0;
-}
-
 /**
  * batadv_interface_set_rx_mode - set the rx mode of a device
  * @dev: registered network device to modify
@@ -920,7 +909,6 @@ static const struct net_device_ops batadv_netdev_ops = {
 	.ndo_vlan_rx_add_vid = batadv_interface_add_vid,
 	.ndo_vlan_rx_kill_vid = batadv_interface_kill_vid,
 	.ndo_set_mac_address = batadv_interface_set_mac_addr,
-	.ndo_change_mtu = batadv_interface_change_mtu,
 	.ndo_set_rx_mode = batadv_interface_set_rx_mode,
 	.ndo_start_xmit = batadv_interface_tx,
 	.ndo_validate_addr = eth_validate_addr,
@@ -987,6 +975,7 @@ struct net_device *batadv_softif_create(struct net *net, const char *name)
 	dev_net_set(soft_iface, net);
 
 	soft_iface->rtnl_link_ops = &batadv_link_ops;
+	soft_iface->max_mtu = batadv_hardif_min_mtu(soft_iface);
 
 	ret = register_netdevice(soft_iface);
 	if (ret < 0) {
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index 89a687f3c0a3..c08e02b67818 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -185,7 +185,7 @@ static struct rtnl_link_stats64 *br_get_stats64(struct net_device *dev,
 static int br_change_mtu(struct net_device *dev, int new_mtu)
 {
 	struct net_bridge *br = netdev_priv(dev);
-	if (new_mtu < 68 || new_mtu > br_min_mtu(br))
+	if (new_mtu > br_min_mtu(br))
 		return -EINVAL;
 
 	dev->mtu = new_mtu;
@@ -410,6 +410,7 @@ void br_dev_setup(struct net_device *dev)
 	br->bridge_hello_time = br->hello_time = 2 * HZ;
 	br->bridge_forward_delay = br->forward_delay = 15 * HZ;
 	br->ageing_time = BR_DEFAULT_AGEING_TIME;
+	dev->max_mtu = ETH_MAX_MTU;
 
 	br_netfilter_rtable_init(br);
 	br_stp_timer_init(br);
diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
index 16737cd8dae8..fc65b145f6e7 100644
--- a/net/hsr/hsr_device.c
+++ b/net/hsr/hsr_device.c
@@ -398,6 +398,7 @@ void hsr_dev_setup(struct net_device *dev)
 	random_ether_addr(dev->dev_addr);
 
 	ether_setup(dev);
+	dev->min_mtu = 0;
 	dev->header_ops = &hsr_header_ops;
 	dev->netdev_ops = &hsr_device_ops;
 	SET_NETDEV_DEVTYPE(dev, &hsr_type);
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) {
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 6a66adba0c22..3a70567846aa 100644
--- 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 8a02ca8a11af..35c5b2d8c401 100644
--- 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 b1cdf8009d29..dc7a3449ffc1 100644
--- 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;
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 638ec0759078..73e6a8fd2845 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -150,15 +150,6 @@ void ieee80211_recalc_idle(struct ieee80211_local *local)
 		ieee80211_hw_config(local, change);
 }
 
-static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
-{
-	if (new_mtu < 256 || new_mtu > IEEE80211_MAX_DATA_LEN)
-		return -EINVAL;
-
-	dev->mtu = new_mtu;
-	return 0;
-}
-
 static int ieee80211_verify_mac(struct ieee80211_sub_if_data *sdata, u8 *addr,
 				bool check_dup)
 {
@@ -1166,7 +1157,6 @@ static const struct net_device_ops ieee80211_dataif_ops = {
 	.ndo_uninit		= ieee80211_uninit,
 	.ndo_start_xmit		= ieee80211_subif_start_xmit,
 	.ndo_set_rx_mode	= ieee80211_set_multicast_list,
-	.ndo_change_mtu 	= ieee80211_change_mtu,
 	.ndo_set_mac_address 	= ieee80211_change_mac,
 	.ndo_select_queue	= ieee80211_netdev_select_queue,
 	.ndo_get_stats64	= ieee80211_get_stats64,
@@ -1200,7 +1190,6 @@ static const struct net_device_ops ieee80211_monitorif_ops = {
 	.ndo_uninit		= ieee80211_uninit,
 	.ndo_start_xmit		= ieee80211_monitor_start_xmit,
 	.ndo_set_rx_mode	= ieee80211_set_multicast_list,
-	.ndo_change_mtu 	= ieee80211_change_mtu,
 	.ndo_set_mac_address 	= ieee80211_change_mac,
 	.ndo_select_queue	= ieee80211_monitor_select_queue,
 	.ndo_get_stats64	= ieee80211_get_stats64,
@@ -1884,6 +1873,10 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 
 		netdev_set_default_ethtool_ops(ndev, &ieee80211_ethtool_ops);
 
+		/* MTU range: 256 - 2304 */
+		ndev->min_mtu = 256;
+		ndev->max_mtu = IEEE80211_MAX_DATA_LEN;
+
 		ret = register_netdevice(ndev);
 		if (ret) {
 			ieee80211_if_free(ndev);
diff --git a/net/openvswitch/vport-internal_dev.c b/net/openvswitch/vport-internal_dev.c
index e7da29021b38..d5d6caecd072 100644
--- a/net/openvswitch/vport-internal_dev.c
+++ b/net/openvswitch/vport-internal_dev.c
@@ -89,15 +89,6 @@ static const struct ethtool_ops internal_dev_ethtool_ops = {
 	.get_link	= ethtool_op_get_link,
 };
 
-static int internal_dev_change_mtu(struct net_device *netdev, int new_mtu)
-{
-	if (new_mtu < 68)
-		return -EINVAL;
-
-	netdev->mtu = new_mtu;
-	return 0;
-}
-
 static void internal_dev_destructor(struct net_device *dev)
 {
 	struct vport *vport = ovs_internal_dev_get_vport(dev);
@@ -148,7 +139,6 @@ static const struct net_device_ops internal_dev_netdev_ops = {
 	.ndo_stop = internal_dev_stop,
 	.ndo_start_xmit = internal_dev_xmit,
 	.ndo_set_mac_address = eth_mac_addr,
-	.ndo_change_mtu = internal_dev_change_mtu,
 	.ndo_get_stats64 = internal_get_stats,
 	.ndo_set_rx_headroom = internal_set_rx_headroom,
 };
diff --git a/net/phonet/pep-gprs.c b/net/phonet/pep-gprs.c
index fa8237fdc57b..21c28b51be94 100644
--- a/net/phonet/pep-gprs.c
+++ b/net/phonet/pep-gprs.c
@@ -217,20 +217,10 @@ static netdev_tx_t gprs_xmit(struct sk_buff *skb, struct net_device *dev)
 	return NETDEV_TX_OK;
 }
 
-static int gprs_set_mtu(struct net_device *dev, int new_mtu)
-{
-	if ((new_mtu < 576) || (new_mtu > (PHONET_MAX_MTU - 11)))
-		return -EINVAL;
-
-	dev->mtu = new_mtu;
-	return 0;
-}
-
 static const struct net_device_ops gprs_netdev_ops = {
 	.ndo_open	= gprs_open,
 	.ndo_stop	= gprs_close,
 	.ndo_start_xmit	= gprs_xmit,
-	.ndo_change_mtu	= gprs_set_mtu,
 };
 
 static void gprs_setup(struct net_device *dev)
@@ -239,6 +229,8 @@ static void gprs_setup(struct net_device *dev)
 	dev->type		= ARPHRD_PHONET_PIPE;
 	dev->flags		= IFF_POINTOPOINT | IFF_NOARP;
 	dev->mtu		= GPRS_DEFAULT_MTU;
+	dev->min_mtu		= 576;
+	dev->max_mtu		= (PHONET_MAX_MTU - 11);
 	dev->hard_header_len	= 0;
 	dev->addr_len		= 0;
 	dev->tx_queue_len	= 10;
diff --git a/net/sched/sch_teql.c b/net/sched/sch_teql.c
index 2cd9b4478b92..b0196366d58d 100644
--- a/net/sched/sch_teql.c
+++ b/net/sched/sch_teql.c
@@ -418,9 +418,6 @@ static int teql_master_mtu(struct net_device *dev, int new_mtu)
 	struct teql_master *m = netdev_priv(dev);
 	struct Qdisc *q;
 
-	if (new_mtu < 68)
-		return -EINVAL;
-
 	q = m->slaves;
 	if (q) {
 		do {
@@ -460,6 +457,8 @@ static __init void teql_master_setup(struct net_device *dev)
 	dev->netdev_ops =       &teql_netdev_ops;
 	dev->type		= ARPHRD_VOID;
 	dev->mtu		= 1500;
+	dev->min_mtu		= 68;
+	dev->max_mtu		= 65535;
 	dev->tx_queue_len	= 100;
 	dev->flags		= IFF_NOARP;
 	dev->hard_header_len	= LL_MAX_HEADER;