diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 6b0e362cc99b..38d906baf1df 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -328,7 +328,7 @@ static int ip_tunnel_bind_dev(struct net_device *dev) if (tdev) { hlen = tdev->hard_header_len + tdev->needed_headroom; - mtu = tdev->mtu; + mtu = min(tdev->mtu, IP_MAX_MTU); } dev->needed_headroom = t_hlen + hlen; @@ -362,7 +362,7 @@ static struct ip_tunnel *ip_tunnel_create(struct net *net, 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; + dev->max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen; ip_tunnel_add(itn, nt); return nt; @@ -930,7 +930,7 @@ 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; + int max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen; if (new_mtu < ETH_MIN_MTU) return -EINVAL; @@ -1107,7 +1107,7 @@ int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], mtu = ip_tunnel_bind_dev(dev); if (tb[IFLA_MTU]) { - unsigned int max = 0xfff8 - dev->hard_header_len - nt->hlen; + unsigned int max = IP_MAX_MTU - dev->hard_header_len - nt->hlen; mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU, (unsigned int)(max - sizeof(struct iphdr))); diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index da66aaac51ce..00e138a44cbb 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -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) - return -EINVAL; + 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; diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 2afce37a7177..e9400ffa7875 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -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; }