diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h index 7c9aadfe8fe3..7fff59bab53b 100644 --- a/include/net/ip_tunnels.h +++ b/include/net/ip_tunnels.h @@ -127,6 +127,7 @@ struct ip_tunnel_6rd_parm { __be32 relay_prefix; u16 prefixlen; u16 relay_prefixlen; + struct rcu_head rcu; }; #endif @@ -185,7 +186,7 @@ struct ip_tunnel { /* for SIT */ #ifdef CONFIG_IPV6_SIT_6RD - struct ip_tunnel_6rd_parm ip6rd; + struct ip_tunnel_6rd_parm __rcu *ip6rd; #endif struct ip_tunnel_prl_entry __rcu *prl; /* potential router list */ unsigned int prl_count; /* # of entries in PRL */ diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index e85fa80e80d1..7cabcd3afbc4 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -183,21 +183,47 @@ static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t) rcu_assign_pointer(*tp, t); } -static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn) +static int ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn) { #ifdef CONFIG_IPV6_SIT_6RD struct ip_tunnel *t = netdev_priv(dev); + struct ip_tunnel_6rd_parm *new_6rd, *old_6rd; + + new_6rd = kmalloc_obj(*new_6rd); + if (!new_6rd) + return -ENOMEM; if (dev == sitn->fb_tunnel_dev || !sitn->fb_tunnel_dev) { - ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0); - t->ip6rd.relay_prefix = 0; - t->ip6rd.prefixlen = 16; - t->ip6rd.relay_prefixlen = 0; + ipv6_addr_set(&new_6rd->prefix, htonl(0x20020000), 0, 0, 0); + new_6rd->relay_prefix = 0; + new_6rd->prefixlen = 16; + new_6rd->relay_prefixlen = 0; } else { struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev); - memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd)); + struct ip_tunnel_6rd_parm *t0_6rd; + + t0_6rd = rtnl_dereference(t0->ip6rd); + if (t0_6rd) { + *new_6rd = *t0_6rd; + } else { + ipv6_addr_set(&new_6rd->prefix, htonl(0x20020000), 0, 0, 0); + new_6rd->relay_prefix = 0; + new_6rd->prefixlen = 16; + new_6rd->relay_prefixlen = 0; + } + } + + old_6rd = rcu_dereference_protected(t->ip6rd, + lockdep_rtnl_is_held() || + dev->reg_state == NETREG_UNINITIALIZED); + rcu_assign_pointer(t->ip6rd, new_6rd); + if (old_6rd) { + dst_cache_reset(&t->dst_cache); + netdev_state_change(t->dev); + kfree_rcu(old_6rd, rcu); } #endif + return 0; } static int ipip6_tunnel_create(struct net_device *dev) @@ -206,6 +232,10 @@ static int ipip6_tunnel_create(struct net_device *dev) struct sit_net *sitn = net_generic(t->net, sit_net_id); int err; + err = ipip6_tunnel_clone_6rd(dev, sitn); + if (err < 0) + goto out; + __dev_addr_set(dev, &t->parms.iph.saddr, 4); memcpy(dev->broadcast, &t->parms.iph.daddr, 4); @@ -218,8 +248,6 @@ static int ipip6_tunnel_create(struct net_device *dev) if (err < 0) goto out; - ipip6_tunnel_clone_6rd(dev, sitn); - ipip6_tunnel_link(sitn, t); return 0; @@ -281,6 +309,7 @@ static struct ip_tunnel *ipip6_tunnel_locate(struct net *net, return nt; failed_free: + ipip6_dev_free(dev); free_netdev(dev); failed: return NULL; @@ -631,8 +660,13 @@ static bool only_dnatted(const struct ip_tunnel *tunnel, int prefix_len; #ifdef CONFIG_IPV6_SIT_6RD - prefix_len = tunnel->ip6rd.prefixlen + 32 - - tunnel->ip6rd.relay_prefixlen; + const struct ip_tunnel_6rd_parm *ip6rd; + + ip6rd = rcu_dereference(tunnel->ip6rd); + if (ip6rd) + prefix_len = ip6rd->prefixlen + 32 - ip6rd->relay_prefixlen; + else + prefix_len = 48; #else prefix_len = 48; #endif @@ -810,25 +844,28 @@ static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, __be32 *v4dst) { #ifdef CONFIG_IPV6_SIT_6RD - if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix, - tunnel->ip6rd.prefixlen)) { + const struct ip_tunnel_6rd_parm *ip6rd; + + ip6rd = rcu_dereference(tunnel->ip6rd); + if (ip6rd && ipv6_prefix_equal(v6dst, &ip6rd->prefix, + ip6rd->prefixlen)) { unsigned int pbw0, pbi0; int pbi1; u32 d; - pbw0 = tunnel->ip6rd.prefixlen >> 5; - pbi0 = tunnel->ip6rd.prefixlen & 0x1f; + pbw0 = ip6rd->prefixlen >> 5; + pbi0 = ip6rd->prefixlen & 0x1f; - d = tunnel->ip6rd.relay_prefixlen < 32 ? + d = ip6rd->relay_prefixlen < 32 ? (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >> - tunnel->ip6rd.relay_prefixlen : 0; + ip6rd->relay_prefixlen : 0; - pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen; + pbi1 = pbi0 - ip6rd->relay_prefixlen; if (pbi1 > 0) d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >> (32 - pbi1); - *v4dst = tunnel->ip6rd.relay_prefix | htonl(d); + *v4dst = ip6rd->relay_prefix | htonl(d); return true; } #else @@ -1164,6 +1201,7 @@ static void ipip6_tunnel_update(struct ip_tunnel *t, static int ipip6_tunnel_update_6rd(struct ip_tunnel *t, struct ip_tunnel_6rd *ip6rd) { + struct ip_tunnel_6rd_parm *new_6rd, *old_6rd; struct in6_addr prefix; __be32 relay_prefix; @@ -1183,10 +1221,20 @@ static int ipip6_tunnel_update_6rd(struct ip_tunnel *t, if (relay_prefix != ip6rd->relay_prefix) return -EINVAL; - t->ip6rd.prefix = prefix; - t->ip6rd.relay_prefix = relay_prefix; - t->ip6rd.prefixlen = ip6rd->prefixlen; - t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen; + new_6rd = kmalloc_obj(*new_6rd); + if (!new_6rd) + return -ENOMEM; + + new_6rd->prefix = prefix; + new_6rd->relay_prefix = relay_prefix; + new_6rd->prefixlen = ip6rd->prefixlen; + new_6rd->relay_prefixlen = ip6rd->relay_prefixlen; + + old_6rd = rtnl_dereference(t->ip6rd); + rcu_assign_pointer(t->ip6rd, new_6rd); + if (old_6rd) + kfree_rcu(old_6rd, rcu); + dst_cache_reset(&t->dst_cache); netdev_state_change(t->dev); return 0; @@ -1195,6 +1243,7 @@ static int ipip6_tunnel_update_6rd(struct ip_tunnel *t, static int ipip6_tunnel_get6rd(struct net_device *dev, struct ip_tunnel_parm __user *data) { + const struct ip_tunnel_6rd_parm *ip6rd_parm; struct ip_tunnel *t = netdev_priv(dev); struct ip_tunnel_parm_kern p; struct ip_tunnel_6rd ip6rd; @@ -1207,10 +1256,15 @@ ipip6_tunnel_get6rd(struct net_device *dev, struct ip_tunnel_parm __user *data) if (!t) t = netdev_priv(dev); - ip6rd.prefix = t->ip6rd.prefix; - ip6rd.relay_prefix = t->ip6rd.relay_prefix; - ip6rd.prefixlen = t->ip6rd.prefixlen; - ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen; + ip6rd_parm = rtnl_dereference(t->ip6rd); + if (ip6rd_parm) { + ip6rd.prefix = ip6rd_parm->prefix; + ip6rd.relay_prefix = ip6rd_parm->relay_prefix; + ip6rd.prefixlen = ip6rd_parm->prefixlen; + ip6rd.relay_prefixlen = ip6rd_parm->relay_prefixlen; + } else { + memset(&ip6rd, 0, sizeof(ip6rd)); + } if (copy_to_user(data, &ip6rd, sizeof(ip6rd))) return -EFAULT; return 0; @@ -1222,20 +1276,16 @@ ipip6_tunnel_6rdctl(struct net_device *dev, struct ip_tunnel_6rd __user *data, { struct ip_tunnel *t = netdev_priv(dev); struct ip_tunnel_6rd ip6rd; - int err; if (!ns_capable(t->net->user_ns, CAP_NET_ADMIN)) return -EPERM; if (copy_from_user(&ip6rd, data, sizeof(ip6rd))) return -EFAULT; - if (cmd != SIOCDEL6RD) { - err = ipip6_tunnel_update_6rd(t, &ip6rd); - if (err < 0) - return err; - } else - ipip6_tunnel_clone_6rd(dev, dev_to_sit_net(dev)); - return 0; + if (cmd != SIOCDEL6RD) + return ipip6_tunnel_update_6rd(t, &ip6rd); + + return ipip6_tunnel_clone_6rd(dev, dev_to_sit_net(dev)); } #endif /* CONFIG_IPV6_SIT_6RD */ @@ -1406,8 +1456,17 @@ static const struct net_device_ops ipip6_netdev_ops = { static void ipip6_dev_free(struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); +#ifdef CONFIG_IPV6_SIT_6RD + struct ip_tunnel_6rd_parm *ip6rd; - dst_cache_destroy(&tunnel->dst_cache); + ip6rd = rcu_dereference_protected(tunnel->ip6rd, 1); + RCU_INIT_POINTER(tunnel->ip6rd, NULL); + kfree(ip6rd); +#endif + if (tunnel->dst_cache.cache) { + dst_cache_destroy(&tunnel->dst_cache); + tunnel->dst_cache.cache = NULL; + } } #define SIT_FEATURES (NETIF_F_SG | \ @@ -1576,8 +1635,10 @@ static int ipip6_newlink(struct net_device *dev, return -EEXIST; err = ipip6_tunnel_create(dev); - if (err < 0) + if (err < 0) { + ipip6_dev_free(dev); return err; + } if (tb[IFLA_MTU]) { u32 mtu = nla_get_u32(tb[IFLA_MTU]); @@ -1695,6 +1756,9 @@ static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); struct ip_tunnel_parm_kern *parm = &tunnel->parms; +#ifdef CONFIG_IPV6_SIT_6RD + const struct ip_tunnel_6rd_parm *ip6rd; +#endif if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) || @@ -1710,14 +1774,16 @@ static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev) goto nla_put_failure; #ifdef CONFIG_IPV6_SIT_6RD - if (nla_put_in6_addr(skb, IFLA_IPTUN_6RD_PREFIX, - &tunnel->ip6rd.prefix) || - nla_put_in_addr(skb, IFLA_IPTUN_6RD_RELAY_PREFIX, - tunnel->ip6rd.relay_prefix) || - nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN, - tunnel->ip6rd.prefixlen) || - nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN, - tunnel->ip6rd.relay_prefixlen)) + ip6rd = rcu_dereference_rtnl(tunnel->ip6rd); + if (ip6rd && + (nla_put_in6_addr(skb, IFLA_IPTUN_6RD_PREFIX, + &ip6rd->prefix) || + nla_put_in_addr(skb, IFLA_IPTUN_6RD_RELAY_PREFIX, + ip6rd->relay_prefix) || + nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN, + ip6rd->prefixlen) || + nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN, + ip6rd->relay_prefixlen))) goto nla_put_failure; #endif @@ -1863,17 +1929,21 @@ static int __net_init sit_init_net(struct net *net) t = netdev_priv(sitn->fb_tunnel_dev); t->net = net; + err = ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn); + if (err < 0) + goto err_reg_dev; + err = register_netdev(sitn->fb_tunnel_dev); if (err) goto err_reg_dev; - ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn); ipip6_fb_tunnel_init(sitn->fb_tunnel_dev); strscpy(t->parms.name, sitn->fb_tunnel_dev->name); return 0; err_reg_dev: + ipip6_dev_free(sitn->fb_tunnel_dev); free_netdev(sitn->fb_tunnel_dev); err_alloc_dev: return err;