diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c index 6b938cc15daf..6ece3c9ccf82 100644 --- a/net/tipc/udp_media.c +++ b/net/tipc/udp_media.c @@ -254,6 +254,26 @@ out: return err; } +static bool tipc_udp_is_known_peer(struct tipc_bearer *b, + struct udp_media_addr *addr) +{ + struct udp_replicast *rcast, *tmp; + struct udp_bearer *ub; + + ub = rcu_dereference_rtnl(b->media_ptr); + if (!ub) { + pr_err_ratelimited("UDP bearer instance not found\n"); + return false; + } + + list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) { + if (!memcmp(&rcast->addr, addr, sizeof(struct udp_media_addr))) + return true; + } + + return false; +} + static int tipc_udp_rcast_add(struct tipc_bearer *b, struct udp_media_addr *addr) { @@ -281,29 +301,83 @@ static int tipc_udp_rcast_add(struct tipc_bearer *b, return 0; } +static int tipc_udp_rcast_disc(struct tipc_bearer *b, struct sk_buff *skb) +{ + struct udp_media_addr src = {0}; + struct udp_media_addr *dst; + + dst = (struct udp_media_addr *)&b->bcast_addr.value; + if (tipc_udp_is_mcast_addr(dst)) + return 0; + + src.port = udp_hdr(skb)->source; + + if (ip_hdr(skb)->version == 4) { + struct iphdr *iphdr = ip_hdr(skb); + + src.proto = htons(ETH_P_IP); + src.ipv4.s_addr = iphdr->saddr; + if (ipv4_is_multicast(iphdr->daddr)) + return 0; +#if IS_ENABLED(CONFIG_IPV6) + } else if (ip_hdr(skb)->version == 6) { + struct ipv6hdr *iphdr = ipv6_hdr(skb); + + src.proto = htons(ETH_P_IPV6); + src.ipv6 = iphdr->saddr; + if (ipv6_addr_is_multicast(&iphdr->daddr)) + return 0; +#endif + } else { + return 0; + } + + if (likely(tipc_udp_is_known_peer(b, &src))) + return 0; + + return tipc_udp_rcast_add(b, &src); +} + /* tipc_udp_recv - read data from bearer socket */ static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb) { struct udp_bearer *ub; struct tipc_bearer *b; + struct tipc_msg *hdr; + int err; ub = rcu_dereference_sk_user_data(sk); if (!ub) { pr_err_ratelimited("Failed to get UDP bearer reference"); - kfree_skb(skb); - return 0; + goto out; } - skb_pull(skb, sizeof(struct udphdr)); + hdr = buf_msg(skb); + rcu_read_lock(); b = rcu_dereference_rtnl(ub->bearer); + if (!b) + goto rcu_out; if (b && test_bit(0, &b->up)) { tipc_rcv(sock_net(sk), skb, b); rcu_read_unlock(); return 0; } + + if (unlikely(msg_user(hdr) == LINK_CONFIG)) { + err = tipc_udp_rcast_disc(b, skb); + if (err) + goto rcu_out; + } + + tipc_rcv(sock_net(sk), skb, b); rcu_read_unlock(); + return 0; + +rcu_out: + rcu_read_unlock(); +out: kfree_skb(skb); return 0; } @@ -398,6 +472,9 @@ int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr) return -EINVAL; } + if (tipc_udp_is_known_peer(b, &addr)) + return 0; + return tipc_udp_rcast_add(b, &addr); }