diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index 0b14ac3b8d1189081967aad8bcbbfce30016aeea..028e3873c3107960c55f0bcff71d860fac0cad6e 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -1039,6 +1039,17 @@ static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev) return geneve_xmit_skb(skb, dev, info); } +static int geneve_change_mtu(struct net_device *dev, int new_mtu) +{ + /* GENEVE overhead is not fixed, so we can't enforce a more + * precise max MTU. + */ + if (new_mtu < 68 || new_mtu > IP_MAX_MTU) + return -EINVAL; + dev->mtu = new_mtu; + return 0; +} + static int geneve_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) { struct ip_tunnel_info *info = skb_tunnel_info(skb); @@ -1083,7 +1094,7 @@ static const struct net_device_ops geneve_netdev_ops = { .ndo_stop = geneve_stop, .ndo_start_xmit = geneve_xmit, .ndo_get_stats64 = ip_tunnel_get_stats64, - .ndo_change_mtu = eth_change_mtu, + .ndo_change_mtu = geneve_change_mtu, .ndo_validate_addr = eth_validate_addr, .ndo_set_mac_address = eth_mac_addr, .ndo_fill_metadata_dst = geneve_fill_metadata_dst, @@ -1442,11 +1453,21 @@ struct net_device *geneve_dev_create_fb(struct net *net, const char *name, err = geneve_configure(net, dev, &geneve_remote_unspec, 0, 0, 0, htons(dst_port), true, 0); - if (err) { - free_netdev(dev); - return ERR_PTR(err); - } + if (err) + goto err; + + /* openvswitch users expect packet sizes to be unrestricted, + * so set the largest MTU we can. + */ + err = geneve_change_mtu(dev, IP_MAX_MTU); + if (err) + goto err; + return dev; + + err: + free_netdev(dev); + return ERR_PTR(err); } EXPORT_SYMBOL_GPL(geneve_dev_create_fb); diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 65439188c5829e1cce0464e6c34be1c8bb5c18c3..a31cd954b308fcf9792df88ec4d1d06842a3b1a1 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -2367,29 +2367,43 @@ static void vxlan_set_multicast_list(struct net_device *dev) { } -static int vxlan_change_mtu(struct net_device *dev, int new_mtu) +static int __vxlan_change_mtu(struct net_device *dev, + struct net_device *lowerdev, + struct vxlan_rdst *dst, int new_mtu, bool strict) { - struct vxlan_dev *vxlan = netdev_priv(dev); - struct vxlan_rdst *dst = &vxlan->default_dst; - struct net_device *lowerdev; - int max_mtu; + int max_mtu = IP_MAX_MTU; - lowerdev = __dev_get_by_index(vxlan->net, dst->remote_ifindex); - if (lowerdev == NULL) - return eth_change_mtu(dev, new_mtu); + if (lowerdev) + max_mtu = lowerdev->mtu; if (dst->remote_ip.sa.sa_family == AF_INET6) - max_mtu = lowerdev->mtu - VXLAN6_HEADROOM; + max_mtu -= VXLAN6_HEADROOM; else - max_mtu = lowerdev->mtu - VXLAN_HEADROOM; + max_mtu -= VXLAN_HEADROOM; - if (new_mtu < 68 || new_mtu > max_mtu) + if (new_mtu < 68) return -EINVAL; + if (new_mtu > max_mtu) { + if (strict) + return -EINVAL; + + new_mtu = max_mtu; + } + dev->mtu = new_mtu; return 0; } +static int vxlan_change_mtu(struct net_device *dev, int new_mtu) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + struct vxlan_rdst *dst = &vxlan->default_dst; + struct net_device *lowerdev = __dev_get_by_index(vxlan->net, + dst->remote_ifindex); + return __vxlan_change_mtu(dev, lowerdev, dst, new_mtu, true); +} + static int egress_ipv4_tun_info(struct net_device *dev, struct sk_buff *skb, struct ip_tunnel_info *info, __be16 sport, __be16 dport) @@ -2765,6 +2779,7 @@ static int vxlan_dev_configure(struct net *src_net, struct net_device *dev, int err; bool use_ipv6 = false; __be16 default_port = vxlan->cfg.dst_port; + struct net_device *lowerdev = NULL; vxlan->net = src_net; @@ -2785,9 +2800,7 @@ static int vxlan_dev_configure(struct net *src_net, struct net_device *dev, } if (conf->remote_ifindex) { - struct net_device *lowerdev - = __dev_get_by_index(src_net, conf->remote_ifindex); - + lowerdev = __dev_get_by_index(src_net, conf->remote_ifindex); dst->remote_ifindex = conf->remote_ifindex; if (!lowerdev) { @@ -2811,6 +2824,12 @@ static int vxlan_dev_configure(struct net *src_net, struct net_device *dev, needed_headroom = lowerdev->hard_header_len; } + if (conf->mtu) { + err = __vxlan_change_mtu(dev, lowerdev, dst, conf->mtu, false); + if (err) + return err; + } + if (use_ipv6 || conf->flags & VXLAN_F_COLLECT_METADATA) needed_headroom += VXLAN6_HEADROOM; else diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h index 6db96ea0144f0445c4e52c51cddcc3d25d60ccdd..dda9abf6b89c14afddf71562c763bdd6bb7d85c3 100644 --- a/include/net/ip_tunnels.h +++ b/include/net/ip_tunnels.h @@ -230,6 +230,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd); int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t, u8 *protocol, struct flowi4 *fl4); +int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict); int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu); struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev, diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 7c51c4e1661f9aafc63829cf58b3b5ec28ed859e..56fdf4e0dce4ef4cb88e34096b4d06cae7de41c5 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -1240,6 +1240,14 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name, err = ipgre_newlink(net, dev, tb, NULL); if (err < 0) goto out; + + /* openvswitch users expect packet sizes to be unrestricted, + * so set the largest MTU we can. + */ + err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); + if (err) + goto out; + return dev; out: free_netdev(dev); diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index c7bd72e9b544848d10a490b010e0a30c4d5e4c21..89e8861e05fcb1d371c371c1784b89499b69d9df 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -943,17 +943,31 @@ int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) } EXPORT_SYMBOL_GPL(ip_tunnel_ioctl); -int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu) +int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict) { struct ip_tunnel *tunnel = netdev_priv(dev); int t_hlen = tunnel->hlen + sizeof(struct iphdr); + int max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen; - if (new_mtu < 68 || - new_mtu > 0xFFF8 - dev->hard_header_len - t_hlen) + if (new_mtu < 68) return -EINVAL; + + if (new_mtu > max_mtu) { + if (strict) + return -EINVAL; + + new_mtu = max_mtu; + } + dev->mtu = new_mtu; return 0; } +EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu); + +int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu) +{ + return __ip_tunnel_change_mtu(dev, new_mtu, true); +} EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu); static void ip_tunnel_dev_free(struct net_device *dev) diff --git a/net/openvswitch/vport-vxlan.c b/net/openvswitch/vport-vxlan.c index 1605691d94144aee0fc50ffb17be05eca2b59675..de9cb19efb6a3e2774624c29b2fe5c977ef92fe4 100644 --- a/net/openvswitch/vport-vxlan.c +++ b/net/openvswitch/vport-vxlan.c @@ -91,6 +91,8 @@ static struct vport *vxlan_tnl_create(const struct vport_parms *parms) struct vxlan_config conf = { .no_share = true, .flags = VXLAN_F_COLLECT_METADATA, + /* Don't restrict the packets that can be sent by MTU */ + .mtu = IP_MAX_MTU, }; if (!options) {