From patchwork Fri Jul 22 19:54:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joanne Koong X-Patchwork-Id: 12926824 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35EF8C43334 for ; Fri, 22 Jul 2022 19:57:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236601AbiGVT5T (ORCPT ); Fri, 22 Jul 2022 15:57:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53044 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236019AbiGVT5Q (ORCPT ); Fri, 22 Jul 2022 15:57:16 -0400 Received: from 66-220-155-178.mail-mxout.facebook.com (66-220-155-178.mail-mxout.facebook.com [66.220.155.178]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC6269C266 for ; Fri, 22 Jul 2022 12:57:13 -0700 (PDT) Received: by devbig010.atn6.facebook.com (Postfix, from userid 115148) id 126E8F53C54E; Fri, 22 Jul 2022 12:56:59 -0700 (PDT) From: Joanne Koong To: netdev@vger.kernel.org Cc: pabeni@redhat.com, edumazet@google.com, kuba@kernel.org, kafai@fb.com, davem@davemloft.net, Joanne Koong Subject: [PATCH net-next v3 1/3] net: Add a bhash2 table hashed by port + address Date: Fri, 22 Jul 2022 12:54:04 -0700 Message-Id: <20220722195406.1304948-2-joannelkoong@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220722195406.1304948-1-joannelkoong@gmail.com> References: <20220722195406.1304948-1-joannelkoong@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The current bind hashtable (bhash) is hashed by port only. In the socket bind path, we have to check for bind conflicts by traversing the specified port's inet_bind_bucket while holding the hashbucket's spinlock (see inet_csk_get_port() and inet_csk_bind_conflict()). In instances where there are tons of sockets hashed to the same port at different addresses, the bind conflict check is time-intensive and can cause softirq cpu lockups, as well as stops new tcp connections since __inet_inherit_port() also contests for the spinlock. This patch adds a second bind table, bhash2, that hashes by port and sk->sk_rcv_saddr (ipv4) and sk->sk_v6_rcv_saddr (ipv6). Searching the bhash2 table leads to significantly faster conflict resolution and less time holding the hashbucket spinlock. Please note a few things: * There can be the case where the a socket's address changes after it has been bound. There are two cases where this happens: 1) The case where there is a bind() call on INADDR_ANY (ipv4) or IPV6_ADDR_ANY (ipv6) and then a connect() call. The kernel will assign the socket an address when it handles the connect() 2) In inet_sk_reselect_saddr(), which is called when rebuilding the sk header and a few pre-conditions are met (eg rerouting fails). In these two cases, we need to update the bhash2 table by removing the entry for the old address, and add a new entry reflecting the updated address. * The bhash2 table must have its own lock, even though concurrent accesses on the same port are protected by the bhash lock. Bhash2 must have its own lock to protect against cases where sockets on different ports hash to different bhash hashbuckets but to the same bhash2 hashbucket. This brings up a few stipulations: 1) When acquiring both the bhash and the bhash2 lock, the bhash2 lock will always be acquired after the bhash lock and released before the bhash lock is released. 2) There are no nested bhash2 hashbucket locks. A bhash2 lock is always acquired+released before another bhash2 lock is acquired+released. * The bhash table cannot be superseded by the bhash2 table because for bind requests on INADDR_ANY (ipv4) or IPV6_ADDR_ANY (ipv6), every socket bound to that port must be checked for a potential conflict. The bhash table is the only source of port->socket associations. Signed-off-by: Joanne Koong Reported-by: kernel test robot Reported-by: kernel test robot --- include/net/inet_connection_sock.h | 3 + include/net/inet_hashtables.h | 80 ++++++++- include/net/sock.h | 14 ++ net/dccp/ipv4.c | 26 ++- net/dccp/ipv6.c | 13 ++ net/dccp/proto.c | 34 +++- net/ipv4/af_inet.c | 27 ++- net/ipv4/inet_connection_sock.c | 275 ++++++++++++++++++++++------- net/ipv4/inet_hashtables.c | 268 ++++++++++++++++++++++++++-- net/ipv4/tcp.c | 11 +- net/ipv4/tcp_ipv4.c | 24 ++- net/ipv6/tcp_ipv6.c | 13 ++ 12 files changed, 694 insertions(+), 94 deletions(-) diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h index 85cd695e7fd1..077cd730ce2f 100644 --- a/include/net/inet_connection_sock.h +++ b/include/net/inet_connection_sock.h @@ -25,6 +25,7 @@ #undef INET_CSK_CLEAR_TIMERS struct inet_bind_bucket; +struct inet_bind2_bucket; struct tcp_congestion_ops; /* @@ -57,6 +58,7 @@ struct inet_connection_sock_af_ops { * * @icsk_accept_queue: FIFO of established children * @icsk_bind_hash: Bind node + * @icsk_bind2_hash: Bind node in the bhash2 table * @icsk_timeout: Timeout * @icsk_retransmit_timer: Resend (no ack) * @icsk_rto: Retransmit timeout @@ -83,6 +85,7 @@ struct inet_connection_sock { struct inet_sock icsk_inet; struct request_sock_queue icsk_accept_queue; struct inet_bind_bucket *icsk_bind_hash; + struct inet_bind2_bucket *icsk_bind2_hash; unsigned long icsk_timeout; struct timer_list icsk_retransmit_timer; struct timer_list icsk_delack_timer; diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h index fd6b510d114b..b18ec7e9ecfc 100644 --- a/include/net/inet_hashtables.h +++ b/include/net/inet_hashtables.h @@ -23,6 +23,7 @@ #include #include +#include #include #include #include @@ -90,7 +91,28 @@ struct inet_bind_bucket { struct hlist_head owners; }; -static inline struct net *ib_net(struct inet_bind_bucket *ib) +struct inet_bind2_bucket { + possible_net_t ib_net; + int l3mdev; + unsigned short port; + union { +#if IS_ENABLED(CONFIG_IPV6) + struct in6_addr v6_rcv_saddr; +#endif + __be32 rcv_saddr; + }; + /* Node in the bhash2 inet_bind_hashbucket chain */ + struct hlist_node node; + /* List of sockets hashed to this bucket */ + struct hlist_head owners; +}; + +static inline struct net *ib_net(const struct inet_bind_bucket *ib) +{ + return read_pnet(&ib->ib_net); +} + +static inline struct net *ib2_net(const struct inet_bind2_bucket *ib) { return read_pnet(&ib->ib_net); } @@ -133,7 +155,14 @@ struct inet_hashinfo { * TCP hash as well as the others for fast bind/connect. */ struct kmem_cache *bind_bucket_cachep; + /* This bind table is hashed by local port */ struct inet_bind_hashbucket *bhash; + struct kmem_cache *bind2_bucket_cachep; + /* This bind table is hashed by local port and sk->sk_rcv_saddr (ipv4) + * or sk->sk_v6_rcv_saddr (ipv6). This 2nd bind table is used + * primarily for expediting bind conflict resolution. + */ + struct inet_bind_hashbucket *bhash2; unsigned int bhash_size; /* The 2nd listener table hashed by local port and address */ @@ -193,14 +222,61 @@ inet_bind_bucket_create(struct kmem_cache *cachep, struct net *net, void inet_bind_bucket_destroy(struct kmem_cache *cachep, struct inet_bind_bucket *tb); +bool inet_bind_bucket_match(const struct inet_bind_bucket *tb, + const struct net *net, unsigned short port, + int l3mdev); + +struct inet_bind2_bucket * +inet_bind2_bucket_create(struct kmem_cache *cachep, struct net *net, + struct inet_bind_hashbucket *head, + unsigned short port, int l3mdev, + const struct sock *sk); + +void inet_bind2_bucket_destroy(struct kmem_cache *cachep, + struct inet_bind2_bucket *tb); + +struct inet_bind2_bucket * +inet_bind2_bucket_find(const struct inet_bind_hashbucket *head, + const struct net *net, + unsigned short port, int l3mdev, + const struct sock *sk); + +bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, + const struct net *net, unsigned short port, + int l3mdev, const struct sock *sk); + static inline u32 inet_bhashfn(const struct net *net, const __u16 lport, const u32 bhash_size) { return (lport + net_hash_mix(net)) & (bhash_size - 1); } +static inline struct inet_bind_hashbucket * +inet_bhashfn_portaddr(const struct inet_hashinfo *hinfo, const struct sock *sk, + const struct net *net, unsigned short port) +{ + u32 hash; + +#if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == AF_INET6) + hash = ipv6_portaddr_hash(net, &sk->sk_v6_rcv_saddr, port); + else +#endif + hash = ipv4_portaddr_hash(net, sk->sk_rcv_saddr, port); + return &hinfo->bhash2[hash & (hinfo->bhash_size - 1)]; +} + +struct inet_bind_hashbucket * +inet_bhash2_addr_any_hashbucket(const struct sock *sk, const struct net *net, int port); + +/* This should be called whenever a socket's sk_rcv_saddr (ipv4) or + * sk_v6_rcv_saddr (ipv6) changes after it has been binded. The socket's + * rcv_saddr field should already have been updated when this is called. + */ +int inet_bhash2_update_saddr(struct inet_bind_hashbucket *prev_saddr, struct sock *sk); + void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb, - const unsigned short snum); + struct inet_bind2_bucket *tb2, unsigned short port); /* Caller must disable local BH processing. */ int __inet_inherit_port(const struct sock *sk, struct sock *child); diff --git a/include/net/sock.h b/include/net/sock.h index f7ad1a7705e9..d8156de55eba 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -348,6 +348,7 @@ struct sk_filter; * @sk_txtime_report_errors: set report errors mode for SO_TXTIME * @sk_txtime_unused: unused txtime flags * @ns_tracker: tracker for netns reference + * @sk_bind2_node: bind node in the bhash2 table */ struct sock { /* @@ -537,6 +538,7 @@ struct sock { #endif struct rcu_head sk_rcu; netns_tracker ns_tracker; + struct hlist_node sk_bind2_node; }; enum sk_pacing { @@ -817,6 +819,16 @@ static inline void sk_add_bind_node(struct sock *sk, hlist_add_head(&sk->sk_bind_node, list); } +static inline void __sk_del_bind2_node(struct sock *sk) +{ + __hlist_del(&sk->sk_bind2_node); +} + +static inline void sk_add_bind2_node(struct sock *sk, struct hlist_head *list) +{ + hlist_add_head(&sk->sk_bind2_node, list); +} + #define sk_for_each(__sk, list) \ hlist_for_each_entry(__sk, list, sk_node) #define sk_for_each_rcu(__sk, list) \ @@ -834,6 +846,8 @@ static inline void sk_add_bind_node(struct sock *sk, hlist_for_each_entry_safe(__sk, tmp, list, sk_node) #define sk_for_each_bound(__sk, list) \ hlist_for_each_entry(__sk, list, sk_bind_node) +#define sk_for_each_bound_bhash2(__sk, list) \ + hlist_for_each_entry(__sk, list, sk_bind2_node) /** * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index da6e3b20cd75..8a7ef5847917 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -45,10 +45,12 @@ static unsigned int dccp_v4_pernet_id __read_mostly; int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; + struct inet_bind_hashbucket *prev_addr_hashbucket = NULL; + __be32 daddr, nexthop, prev_sk_rcv_saddr; struct inet_sock *inet = inet_sk(sk); struct dccp_sock *dp = dccp_sk(sk); __be16 orig_sport, orig_dport; - __be32 daddr, nexthop; + bool new_sk_saddr = false; struct flowi4 *fl4; struct rtable *rt; int err; @@ -89,9 +91,29 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) if (inet_opt == NULL || !inet_opt->opt.srr) daddr = fl4->daddr; - if (inet->inet_saddr == 0) + if (inet->inet_saddr == 0) { + if (inet_csk(sk)->icsk_bind2_hash) + prev_addr_hashbucket = + inet_bhashfn_portaddr(&dccp_hashinfo, sk, + sock_net(sk), + inet->inet_num); + prev_sk_rcv_saddr = sk->sk_rcv_saddr; inet->inet_saddr = fl4->saddr; + new_sk_saddr = true; + } + sk_rcv_saddr_set(sk, inet->inet_saddr); + + if (new_sk_saddr) { + err = inet_bhash2_update_saddr(prev_addr_hashbucket, sk); + if (err) { + inet->inet_saddr = 0; + sk_rcv_saddr_set(sk, prev_sk_rcv_saddr); + ip_rt_put(rt); + return err; + } + } + inet->inet_dport = usin->sin_port; sk_daddr_set(sk, daddr); diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c index fd44638ec16b..503d8e83ac52 100644 --- a/net/dccp/ipv6.c +++ b/net/dccp/ipv6.c @@ -934,8 +934,21 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr, } if (saddr == NULL) { + struct in6_addr prev_v6_rcv_saddr = sk->sk_v6_rcv_saddr; + struct inet_bind_hashbucket *prev_addr_hashbucket = NULL; + + if (icsk->icsk_bind2_hash) + prev_addr_hashbucket = inet_bhashfn_portaddr(&dccp_hashinfo, + sk, sock_net(sk), + inet->inet_num); saddr = &fl6.saddr; sk->sk_v6_rcv_saddr = *saddr; + + err = inet_bhash2_update_saddr(prev_addr_hashbucket, sk); + if (err) { + sk->sk_v6_rcv_saddr = prev_v6_rcv_saddr; + goto failure; + } } /* set the source address */ diff --git a/net/dccp/proto.c b/net/dccp/proto.c index eb8e128e43e8..f4f2ad5f9c08 100644 --- a/net/dccp/proto.c +++ b/net/dccp/proto.c @@ -1120,6 +1120,12 @@ static int __init dccp_init(void) SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, NULL); if (!dccp_hashinfo.bind_bucket_cachep) goto out_free_hashinfo2; + dccp_hashinfo.bind2_bucket_cachep = + kmem_cache_create("dccp_bind2_bucket", + sizeof(struct inet_bind2_bucket), 0, + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, NULL); + if (!dccp_hashinfo.bind2_bucket_cachep) + goto out_free_bind_bucket_cachep; /* * Size and allocate the main established and bind bucket @@ -1150,7 +1156,7 @@ static int __init dccp_init(void) if (!dccp_hashinfo.ehash) { DCCP_CRIT("Failed to allocate DCCP established hash table"); - goto out_free_bind_bucket_cachep; + goto out_free_bind2_bucket_cachep; } for (i = 0; i <= dccp_hashinfo.ehash_mask; i++) @@ -1176,14 +1182,24 @@ static int __init dccp_init(void) goto out_free_dccp_locks; } + dccp_hashinfo.bhash2 = (struct inet_bind_hashbucket *) + __get_free_pages(GFP_ATOMIC | __GFP_NOWARN, bhash_order); + + if (!dccp_hashinfo.bhash2) { + DCCP_CRIT("Failed to allocate DCCP bind2 hash table"); + goto out_free_dccp_bhash; + } + for (i = 0; i < dccp_hashinfo.bhash_size; i++) { spin_lock_init(&dccp_hashinfo.bhash[i].lock); INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain); + spin_lock_init(&dccp_hashinfo.bhash2[i].lock); + INIT_HLIST_HEAD(&dccp_hashinfo.bhash2[i].chain); } rc = dccp_mib_init(); if (rc) - goto out_free_dccp_bhash; + goto out_free_dccp_bhash2; rc = dccp_ackvec_init(); if (rc) @@ -1207,30 +1223,38 @@ static int __init dccp_init(void) dccp_ackvec_exit(); out_free_dccp_mib: dccp_mib_exit(); +out_free_dccp_bhash2: + free_pages((unsigned long)dccp_hashinfo.bhash2, bhash_order); out_free_dccp_bhash: free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order); out_free_dccp_locks: inet_ehash_locks_free(&dccp_hashinfo); out_free_dccp_ehash: free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order); +out_free_bind2_bucket_cachep: + kmem_cache_destroy(dccp_hashinfo.bind2_bucket_cachep); out_free_bind_bucket_cachep: kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep); out_free_hashinfo2: inet_hashinfo2_free_mod(&dccp_hashinfo); out_fail: dccp_hashinfo.bhash = NULL; + dccp_hashinfo.bhash2 = NULL; dccp_hashinfo.ehash = NULL; dccp_hashinfo.bind_bucket_cachep = NULL; + dccp_hashinfo.bind2_bucket_cachep = NULL; return rc; } static void __exit dccp_fini(void) { + int bhash_order = get_order(dccp_hashinfo.bhash_size * + sizeof(struct inet_bind_hashbucket)); + ccid_cleanup_builtins(); dccp_mib_exit(); - free_pages((unsigned long)dccp_hashinfo.bhash, - get_order(dccp_hashinfo.bhash_size * - sizeof(struct inet_bind_hashbucket))); + free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order); + free_pages((unsigned long)dccp_hashinfo.bhash2, bhash_order); free_pages((unsigned long)dccp_hashinfo.ehash, get_order((dccp_hashinfo.ehash_mask + 1) * sizeof(struct inet_ehash_bucket))); diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 3ca0cc467886..c40b47ee1a36 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1219,6 +1219,7 @@ EXPORT_SYMBOL(inet_unregister_protosw); static int inet_sk_reselect_saddr(struct sock *sk) { + struct inet_bind_hashbucket *prev_addr_hashbucket = NULL; struct inet_sock *inet = inet_sk(sk); __be32 old_saddr = inet->inet_saddr; __be32 daddr = inet->inet_daddr; @@ -1226,6 +1227,7 @@ static int inet_sk_reselect_saddr(struct sock *sk) struct rtable *rt; __be32 new_saddr; struct ip_options_rcu *inet_opt; + int err; inet_opt = rcu_dereference_protected(inet->inet_opt, lockdep_sock_is_held(sk)); @@ -1240,20 +1242,35 @@ static int inet_sk_reselect_saddr(struct sock *sk) if (IS_ERR(rt)) return PTR_ERR(rt); - sk_setup_caps(sk, &rt->dst); - new_saddr = fl4->saddr; - if (new_saddr == old_saddr) + if (new_saddr == old_saddr) { + sk_setup_caps(sk, &rt->dst); return 0; + } + + if (inet_csk(sk)->icsk_bind2_hash) + prev_addr_hashbucket = + inet_bhashfn_portaddr(sk->sk_prot->h.hashinfo, sk, + sock_net(sk), inet->inet_num); + + inet->inet_saddr = inet->inet_rcv_saddr = new_saddr; + + err = inet_bhash2_update_saddr(prev_addr_hashbucket, sk); + if (err) { + inet->inet_saddr = old_saddr; + inet->inet_rcv_saddr = old_saddr; + ip_rt_put(rt); + return err; + } + + sk_setup_caps(sk, &rt->dst); if (READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) > 1) { pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n", __func__, &old_saddr, &new_saddr); } - inet->inet_saddr = inet->inet_rcv_saddr = new_saddr; - /* * XXX The only one ugly spot where we need to * XXX really change the sockets identity after diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index eb31c7158b39..f0038043b661 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -130,14 +130,75 @@ void inet_get_local_port_range(struct net *net, int *low, int *high) } EXPORT_SYMBOL(inet_get_local_port_range); +static bool inet_use_bhash2_on_bind(const struct sock *sk) +{ +#if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == AF_INET6) { + int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr); + + return addr_type != IPV6_ADDR_ANY && + addr_type != IPV6_ADDR_MAPPED; + } +#endif + return sk->sk_rcv_saddr != htonl(INADDR_ANY); +} + +static bool inet_bind_conflict(const struct sock *sk, struct sock *sk2, + kuid_t sk_uid, bool relax, + bool reuseport_cb_ok, bool reuseport_ok) +{ + int bound_dev_if2; + + if (sk == sk2) + return false; + + bound_dev_if2 = READ_ONCE(sk2->sk_bound_dev_if); + + if (!sk->sk_bound_dev_if || !bound_dev_if2 || + sk->sk_bound_dev_if == bound_dev_if2) { + if (sk->sk_reuse && sk2->sk_reuse && + sk2->sk_state != TCP_LISTEN) { + if (!relax || (!reuseport_ok && sk->sk_reuseport && + sk2->sk_reuseport && reuseport_cb_ok && + (sk2->sk_state == TCP_TIME_WAIT || + uid_eq(sk_uid, sock_i_uid(sk2))))) + return true; + } else if (!reuseport_ok || !sk->sk_reuseport || + !sk2->sk_reuseport || !reuseport_cb_ok || + (sk2->sk_state != TCP_TIME_WAIT && + !uid_eq(sk_uid, sock_i_uid(sk2)))) { + return true; + } + } + return false; +} + +static bool inet_bhash2_conflict(const struct sock *sk, + const struct inet_bind2_bucket *tb2, + kuid_t sk_uid, + bool relax, bool reuseport_cb_ok, + bool reuseport_ok) +{ + struct sock *sk2; + + sk_for_each_bound_bhash2(sk2, &tb2->owners) { + if (sk->sk_family == AF_INET && ipv6_only_sock(sk2)) + continue; + + if (inet_bind_conflict(sk, sk2, sk_uid, relax, + reuseport_cb_ok, reuseport_ok)) + return true; + } + return false; +} + +/* This should be called only when the tb and tb2 hashbuckets' locks are held */ static int inet_csk_bind_conflict(const struct sock *sk, const struct inet_bind_bucket *tb, + const struct inet_bind2_bucket *tb2, /* may be null */ bool relax, bool reuseport_ok) { - struct sock *sk2; bool reuseport_cb_ok; - bool reuse = sk->sk_reuse; - bool reuseport = !!sk->sk_reuseport; struct sock_reuseport *reuseport_cb; kuid_t uid = sock_i_uid((struct sock *)sk); @@ -150,55 +211,87 @@ static int inet_csk_bind_conflict(const struct sock *sk, /* * Unlike other sk lookup places we do not check * for sk_net here, since _all_ the socks listed - * in tb->owners list belong to the same net - the - * one this bucket belongs to. + * in tb->owners and tb2->owners list belong + * to the same net - the one this bucket belongs to. */ - sk_for_each_bound(sk2, &tb->owners) { - int bound_dev_if2; + if (!inet_use_bhash2_on_bind(sk)) { + struct sock *sk2; - if (sk == sk2) - continue; - bound_dev_if2 = READ_ONCE(sk2->sk_bound_dev_if); - if ((!sk->sk_bound_dev_if || - !bound_dev_if2 || - sk->sk_bound_dev_if == bound_dev_if2)) { - if (reuse && sk2->sk_reuse && - sk2->sk_state != TCP_LISTEN) { - if ((!relax || - (!reuseport_ok && - reuseport && sk2->sk_reuseport && - reuseport_cb_ok && - (sk2->sk_state == TCP_TIME_WAIT || - uid_eq(uid, sock_i_uid(sk2))))) && - inet_rcv_saddr_equal(sk, sk2, true)) - break; - } else if (!reuseport_ok || - !reuseport || !sk2->sk_reuseport || - !reuseport_cb_ok || - (sk2->sk_state != TCP_TIME_WAIT && - !uid_eq(uid, sock_i_uid(sk2)))) { - if (inet_rcv_saddr_equal(sk, sk2, true)) - break; - } - } + sk_for_each_bound(sk2, &tb->owners) + if (inet_bind_conflict(sk, sk2, uid, relax, + reuseport_cb_ok, reuseport_ok) && + inet_rcv_saddr_equal(sk, sk2, true)) + return true; + + return false; + } + + /* Conflicts with an existing IPV6_ADDR_ANY (if ipv6) or INADDR_ANY (if + * ipv4) should have been checked already. We need to do these two + * checks separately because their spinlocks have to be acquired/released + * independently of each other, to prevent possible deadlocks + */ + return tb2 && inet_bhash2_conflict(sk, tb2, uid, relax, reuseport_cb_ok, + reuseport_ok); +} + +/* Determine if there is a bind conflict with an existing IPV6_ADDR_ANY (if ipv6) or + * INADDR_ANY (if ipv4) socket. + * + * Caller must hold bhash hashbucket lock with local bh disabled, to protect + * against concurrent binds on the port for addr any + */ +static bool inet_bhash2_addr_any_conflict(const struct sock *sk, int port, int l3mdev, + bool relax, bool reuseport_ok) +{ + kuid_t uid = sock_i_uid((struct sock *)sk); + const struct net *net = sock_net(sk); + struct sock_reuseport *reuseport_cb; + struct inet_bind_hashbucket *head2; + struct inet_bind2_bucket *tb2; + bool reuseport_cb_ok; + + rcu_read_lock(); + reuseport_cb = rcu_dereference(sk->sk_reuseport_cb); + /* paired with WRITE_ONCE() in __reuseport_(add|detach)_closed_sock */ + reuseport_cb_ok = !reuseport_cb || READ_ONCE(reuseport_cb->num_closed_socks); + rcu_read_unlock(); + + head2 = inet_bhash2_addr_any_hashbucket(sk, net, port); + + spin_lock(&head2->lock); + + inet_bind_bucket_for_each(tb2, &head2->chain) + if (inet_bind2_bucket_match_addr_any(tb2, net, port, l3mdev, sk)) + break; + + if (tb2 && inet_bhash2_conflict(sk, tb2, uid, relax, reuseport_cb_ok, + reuseport_ok)) { + spin_unlock(&head2->lock); + return true; } - return sk2 != NULL; + + spin_unlock(&head2->lock); + return false; } /* * Find an open port number for the socket. Returns with the - * inet_bind_hashbucket lock held. + * inet_bind_hashbucket locks held if successful. */ static struct inet_bind_hashbucket * -inet_csk_find_open_port(struct sock *sk, struct inet_bind_bucket **tb_ret, int *port_ret) +inet_csk_find_open_port(const struct sock *sk, struct inet_bind_bucket **tb_ret, + struct inet_bind2_bucket **tb2_ret, + struct inet_bind_hashbucket **head2_ret, int *port_ret) { struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo; int port = 0; - struct inet_bind_hashbucket *head; + struct inet_bind_hashbucket *head, *head2; struct net *net = sock_net(sk); bool relax = false; int i, low, high, attempt_half; + struct inet_bind2_bucket *tb2; struct inet_bind_bucket *tb; u32 remaining, offset; int l3mdev; @@ -239,11 +332,20 @@ inet_csk_find_open_port(struct sock *sk, struct inet_bind_bucket **tb_ret, int * head = &hinfo->bhash[inet_bhashfn(net, port, hinfo->bhash_size)]; spin_lock_bh(&head->lock); + if (inet_use_bhash2_on_bind(sk)) { + if (inet_bhash2_addr_any_conflict(sk, port, l3mdev, relax, false)) + goto next_port; + } + + head2 = inet_bhashfn_portaddr(hinfo, sk, net, port); + spin_lock(&head2->lock); + tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk); inet_bind_bucket_for_each(tb, &head->chain) - if (net_eq(ib_net(tb), net) && tb->l3mdev == l3mdev && - tb->port == port) { - if (!inet_csk_bind_conflict(sk, tb, relax, false)) + if (inet_bind_bucket_match(tb, net, port, l3mdev)) { + if (!inet_csk_bind_conflict(sk, tb, tb2, + relax, false)) goto success; + spin_unlock(&head2->lock); goto next_port; } tb = NULL; @@ -272,6 +374,8 @@ inet_csk_find_open_port(struct sock *sk, struct inet_bind_bucket **tb_ret, int * success: *port_ret = port; *tb_ret = tb; + *tb2_ret = tb2; + *head2_ret = head2; return head; } @@ -368,53 +472,95 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum) bool reuse = sk->sk_reuse && sk->sk_state != TCP_LISTEN; struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo; int ret = 1, port = snum; - struct inet_bind_hashbucket *head; struct net *net = sock_net(sk); + bool found_port = false, check_bind_conflict = true; + bool bhash_created = false, bhash2_created = false; + struct inet_bind_hashbucket *head, *head2; + struct inet_bind2_bucket *tb2 = NULL; struct inet_bind_bucket *tb = NULL; + bool head2_lock_acquired = false; int l3mdev; l3mdev = inet_sk_bound_l3mdev(sk); if (!port) { - head = inet_csk_find_open_port(sk, &tb, &port); + head = inet_csk_find_open_port(sk, &tb, &tb2, &head2, &port); if (!head) return ret; + + head2_lock_acquired = true; + + if (tb && tb2) + goto success; + found_port = true; + } else { + head = &hinfo->bhash[inet_bhashfn(net, port, + hinfo->bhash_size)]; + spin_lock_bh(&head->lock); + inet_bind_bucket_for_each(tb, &head->chain) + if (inet_bind_bucket_match(tb, net, port, l3mdev)) + break; + } + + if (!tb) { + tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep, net, + head, port, l3mdev); if (!tb) - goto tb_not_found; - goto success; + goto fail_unlock; + bhash_created = true; } - head = &hinfo->bhash[inet_bhashfn(net, port, - hinfo->bhash_size)]; - spin_lock_bh(&head->lock); - inet_bind_bucket_for_each(tb, &head->chain) - if (net_eq(ib_net(tb), net) && tb->l3mdev == l3mdev && - tb->port == port) - goto tb_found; -tb_not_found: - tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep, - net, head, port, l3mdev); - if (!tb) - goto fail_unlock; -tb_found: - if (!hlist_empty(&tb->owners)) { - if (sk->sk_reuse == SK_FORCE_REUSE) - goto success; - if ((tb->fastreuse > 0 && reuse) || - sk_reuseport_match(tb, sk)) - goto success; - if (inet_csk_bind_conflict(sk, tb, true, true)) + if (!found_port) { + if (!hlist_empty(&tb->owners)) { + if (sk->sk_reuse == SK_FORCE_REUSE || + (tb->fastreuse > 0 && reuse) || + sk_reuseport_match(tb, sk)) + check_bind_conflict = false; + } + + if (check_bind_conflict && inet_use_bhash2_on_bind(sk)) { + if (inet_bhash2_addr_any_conflict(sk, port, l3mdev, true, true)) + goto fail_unlock; + } + + head2 = inet_bhashfn_portaddr(hinfo, sk, net, port); + spin_lock(&head2->lock); + head2_lock_acquired = true; + tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk); + } + + if (!tb2) { + tb2 = inet_bind2_bucket_create(hinfo->bind2_bucket_cachep, + net, head2, port, l3mdev, sk); + if (!tb2) goto fail_unlock; + bhash2_created = true; } + + if (!found_port && check_bind_conflict) { + if (inet_csk_bind_conflict(sk, tb, tb2, true, true)) + goto fail_unlock; + } + success: inet_csk_update_fastreuse(tb, sk); if (!inet_csk(sk)->icsk_bind_hash) - inet_bind_hash(sk, tb, port); + inet_bind_hash(sk, tb, tb2, port); WARN_ON(inet_csk(sk)->icsk_bind_hash != tb); + WARN_ON(inet_csk(sk)->icsk_bind2_hash != tb2); ret = 0; fail_unlock: + if (ret) { + if (bhash_created) + inet_bind_bucket_destroy(hinfo->bind_bucket_cachep, tb); + if (bhash2_created) + inet_bind2_bucket_destroy(hinfo->bind2_bucket_cachep, + tb2); + } + if (head2_lock_acquired) + spin_unlock(&head2->lock); spin_unlock_bh(&head->lock); return ret; } @@ -962,6 +1108,7 @@ struct sock *inet_csk_clone_lock(const struct sock *sk, inet_sk_set_state(newsk, TCP_SYN_RECV); newicsk->icsk_bind_hash = NULL; + newicsk->icsk_bind2_hash = NULL; inet_sk(newsk)->inet_dport = inet_rsk(req)->ir_rmt_port; inet_sk(newsk)->inet_num = inet_rsk(req)->ir_num; diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index b9d995b5ce24..60d77e234a68 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -92,12 +92,75 @@ void inet_bind_bucket_destroy(struct kmem_cache *cachep, struct inet_bind_bucket } } +bool inet_bind_bucket_match(const struct inet_bind_bucket *tb, const struct net *net, + unsigned short port, int l3mdev) +{ + return net_eq(ib_net(tb), net) && tb->port == port && + tb->l3mdev == l3mdev; +} + +static void inet_bind2_bucket_init(struct inet_bind2_bucket *tb, + struct net *net, + struct inet_bind_hashbucket *head, + unsigned short port, int l3mdev, + const struct sock *sk) +{ + write_pnet(&tb->ib_net, net); + tb->l3mdev = l3mdev; + tb->port = port; +#if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == AF_INET6) + tb->v6_rcv_saddr = sk->sk_v6_rcv_saddr; + else +#endif + tb->rcv_saddr = sk->sk_rcv_saddr; + INIT_HLIST_HEAD(&tb->owners); + hlist_add_head(&tb->node, &head->chain); +} + +struct inet_bind2_bucket *inet_bind2_bucket_create(struct kmem_cache *cachep, + struct net *net, + struct inet_bind_hashbucket *head, + unsigned short port, + int l3mdev, + const struct sock *sk) +{ + struct inet_bind2_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC); + + if (tb) + inet_bind2_bucket_init(tb, net, head, port, l3mdev, sk); + + return tb; +} + +/* Caller must hold hashbucket lock for this tb with local BH disabled */ +void inet_bind2_bucket_destroy(struct kmem_cache *cachep, struct inet_bind2_bucket *tb) +{ + if (hlist_empty(&tb->owners)) { + __hlist_del(&tb->node); + kmem_cache_free(cachep, tb); + } +} + +static bool inet_bind2_bucket_addr_match(const struct inet_bind2_bucket *tb2, + const struct sock *sk) +{ +#if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == AF_INET6) + return ipv6_addr_equal(&tb2->v6_rcv_saddr, + &sk->sk_v6_rcv_saddr); +#endif + return tb2->rcv_saddr == sk->sk_rcv_saddr; +} + void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb, - const unsigned short snum) + struct inet_bind2_bucket *tb2, unsigned short port) { - inet_sk(sk)->inet_num = snum; + inet_sk(sk)->inet_num = port; sk_add_bind_node(sk, &tb->owners); inet_csk(sk)->icsk_bind_hash = tb; + sk_add_bind2_node(sk, &tb2->owners); + inet_csk(sk)->icsk_bind2_hash = tb2; } /* @@ -109,6 +172,9 @@ static void __inet_put_port(struct sock *sk) const int bhash = inet_bhashfn(sock_net(sk), inet_sk(sk)->inet_num, hashinfo->bhash_size); struct inet_bind_hashbucket *head = &hashinfo->bhash[bhash]; + struct inet_bind_hashbucket *head2 = + inet_bhashfn_portaddr(hashinfo, sk, sock_net(sk), + inet_sk(sk)->inet_num); struct inet_bind_bucket *tb; spin_lock(&head->lock); @@ -117,6 +183,17 @@ static void __inet_put_port(struct sock *sk) inet_csk(sk)->icsk_bind_hash = NULL; inet_sk(sk)->inet_num = 0; inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb); + + spin_lock(&head2->lock); + if (inet_csk(sk)->icsk_bind2_hash) { + struct inet_bind2_bucket *tb2 = inet_csk(sk)->icsk_bind2_hash; + + __sk_del_bind2_node(sk); + inet_csk(sk)->icsk_bind2_hash = NULL; + inet_bind2_bucket_destroy(hashinfo->bind2_bucket_cachep, tb2); + } + spin_unlock(&head2->lock); + spin_unlock(&head->lock); } @@ -135,12 +212,21 @@ int __inet_inherit_port(const struct sock *sk, struct sock *child) const int bhash = inet_bhashfn(sock_net(sk), port, table->bhash_size); struct inet_bind_hashbucket *head = &table->bhash[bhash]; + struct inet_bind_hashbucket *head2 = + inet_bhashfn_portaddr(table, child, sock_net(sk), port); + bool created_inet_bind_bucket = false; + bool update_fastreuse = false; + struct net *net = sock_net(sk); + struct inet_bind2_bucket *tb2; struct inet_bind_bucket *tb; int l3mdev; spin_lock(&head->lock); + spin_lock(&head2->lock); tb = inet_csk(sk)->icsk_bind_hash; - if (unlikely(!tb)) { + tb2 = inet_csk(sk)->icsk_bind2_hash; + if (unlikely(!tb || !tb2)) { + spin_unlock(&head2->lock); spin_unlock(&head->lock); return -ENOENT; } @@ -153,25 +239,49 @@ int __inet_inherit_port(const struct sock *sk, struct sock *child) * as that of the child socket. We have to look up or * create a new bind bucket for the child here. */ inet_bind_bucket_for_each(tb, &head->chain) { - if (net_eq(ib_net(tb), sock_net(sk)) && - tb->l3mdev == l3mdev && tb->port == port) + if (inet_bind_bucket_match(tb, net, port, l3mdev)) break; } if (!tb) { tb = inet_bind_bucket_create(table->bind_bucket_cachep, - sock_net(sk), head, port, - l3mdev); + net, head, port, l3mdev); if (!tb) { + spin_unlock(&head2->lock); spin_unlock(&head->lock); return -ENOMEM; } + created_inet_bind_bucket = true; + } + update_fastreuse = true; + + goto bhash2_find; + } else if (!inet_bind2_bucket_addr_match(tb2, child)) { + l3mdev = inet_sk_bound_l3mdev(sk); + +bhash2_find: + tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, child); + if (!tb2) { + tb2 = inet_bind2_bucket_create(table->bind2_bucket_cachep, + net, head2, port, + l3mdev, child); + if (!tb2) + goto error; } - inet_csk_update_fastreuse(tb, child); } - inet_bind_hash(child, tb, port); + if (update_fastreuse) + inet_csk_update_fastreuse(tb, child); + inet_bind_hash(child, tb, tb2, port); + spin_unlock(&head2->lock); spin_unlock(&head->lock); return 0; + +error: + if (created_inet_bind_bucket) + inet_bind_bucket_destroy(table->bind_bucket_cachep, tb); + spin_unlock(&head2->lock); + spin_unlock(&head->lock); + return -ENOMEM; } EXPORT_SYMBOL_GPL(__inet_inherit_port); @@ -675,6 +785,112 @@ void inet_unhash(struct sock *sk) } EXPORT_SYMBOL_GPL(inet_unhash); +static bool inet_bind2_bucket_match(const struct inet_bind2_bucket *tb, + const struct net *net, unsigned short port, + int l3mdev, const struct sock *sk) +{ +#if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == AF_INET6) + return net_eq(ib2_net(tb), net) && tb->port == port && + tb->l3mdev == l3mdev && + ipv6_addr_equal(&tb->v6_rcv_saddr, &sk->sk_v6_rcv_saddr); + else +#endif + return net_eq(ib2_net(tb), net) && tb->port == port && + tb->l3mdev == l3mdev && tb->rcv_saddr == sk->sk_rcv_saddr; +} + +bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const struct net *net, + unsigned short port, int l3mdev, const struct sock *sk) +{ +#if IS_ENABLED(CONFIG_IPV6) + struct in6_addr addr_any = {}; + + if (sk->sk_family == AF_INET6) + return net_eq(ib2_net(tb), net) && tb->port == port && + tb->l3mdev == l3mdev && + ipv6_addr_equal(&tb->v6_rcv_saddr, &addr_any); + else +#endif + return net_eq(ib2_net(tb), net) && tb->port == port && + tb->l3mdev == l3mdev && tb->rcv_saddr == 0; +} + +/* The socket's bhash2 hashbucket spinlock must be held when this is called */ +struct inet_bind2_bucket * +inet_bind2_bucket_find(const struct inet_bind_hashbucket *head, const struct net *net, + unsigned short port, int l3mdev, const struct sock *sk) +{ + struct inet_bind2_bucket *bhash2 = NULL; + + inet_bind_bucket_for_each(bhash2, &head->chain) + if (inet_bind2_bucket_match(bhash2, net, port, l3mdev, sk)) + break; + + return bhash2; +} + +struct inet_bind_hashbucket * +inet_bhash2_addr_any_hashbucket(const struct sock *sk, const struct net *net, int port) +{ + struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo; + u32 hash; +#if IS_ENABLED(CONFIG_IPV6) + struct in6_addr addr_any = {}; + + if (sk->sk_family == AF_INET6) + hash = ipv6_portaddr_hash(net, &addr_any, port); + else +#endif + hash = ipv4_portaddr_hash(net, 0, port); + + return &hinfo->bhash2[hash & (hinfo->bhash_size - 1)]; +} + +int inet_bhash2_update_saddr(struct inet_bind_hashbucket *prev_saddr, struct sock *sk) +{ + struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo; + struct inet_bind2_bucket *tb2, *new_tb2; + int l3mdev = inet_sk_bound_l3mdev(sk); + struct inet_bind_hashbucket *head2; + int port = inet_sk(sk)->inet_num; + struct net *net = sock_net(sk); + + /* Allocate a bind2 bucket ahead of time to avoid permanently putting + * the bhash2 table in an inconsistent state if a new tb2 bucket + * allocation fails. + */ + new_tb2 = kmem_cache_alloc(hinfo->bind2_bucket_cachep, GFP_ATOMIC); + if (!new_tb2) + return -ENOMEM; + + head2 = inet_bhashfn_portaddr(hinfo, sk, net, port); + + if (prev_saddr) { + spin_lock_bh(&prev_saddr->lock); + __sk_del_bind2_node(sk); + inet_bind2_bucket_destroy(hinfo->bind2_bucket_cachep, + inet_csk(sk)->icsk_bind2_hash); + spin_unlock_bh(&prev_saddr->lock); + } + + spin_lock_bh(&head2->lock); + tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk); + if (!tb2) { + tb2 = new_tb2; + inet_bind2_bucket_init(tb2, net, head2, port, l3mdev, sk); + } + sk_add_bind2_node(sk, &tb2->owners); + inet_csk(sk)->icsk_bind2_hash = tb2; + spin_unlock_bh(&head2->lock); + + if (tb2 != new_tb2) + kmem_cache_free(hinfo->bind2_bucket_cachep, new_tb2); + + return 0; +} +EXPORT_SYMBOL_GPL(inet_bhash2_update_saddr); + /* RFC 6056 3.3.4. Algorithm 4: Double-Hash Port Selection Algorithm * Note that we use 32bit integers (vs RFC 'short integers') * because 2^16 is not a multiple of num_ephemeral and this @@ -694,11 +910,13 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, struct sock *, __u16, struct inet_timewait_sock **)) { struct inet_hashinfo *hinfo = death_row->hashinfo; + struct inet_bind_hashbucket *head, *head2; struct inet_timewait_sock *tw = NULL; - struct inet_bind_hashbucket *head; int port = inet_sk(sk)->inet_num; struct net *net = sock_net(sk); + struct inet_bind2_bucket *tb2; struct inet_bind_bucket *tb; + bool tb_created = false; u32 remaining, offset; int ret, i, low, high; int l3mdev; @@ -755,8 +973,7 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, * the established check is already unique enough. */ inet_bind_bucket_for_each(tb, &head->chain) { - if (net_eq(ib_net(tb), net) && tb->l3mdev == l3mdev && - tb->port == port) { + if (inet_bind_bucket_match(tb, net, port, l3mdev)) { if (tb->fastreuse >= 0 || tb->fastreuseport >= 0) goto next_port; @@ -774,6 +991,7 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, spin_unlock_bh(&head->lock); return -ENOMEM; } + tb_created = true; tb->fastreuse = -1; tb->fastreuseport = -1; goto ok; @@ -789,6 +1007,20 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, return -EADDRNOTAVAIL; ok: + /* Find the corresponding tb2 bucket since we need to + * add the socket to the bhash2 table as well + */ + head2 = inet_bhashfn_portaddr(hinfo, sk, net, port); + spin_lock(&head2->lock); + + tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk); + if (!tb2) { + tb2 = inet_bind2_bucket_create(hinfo->bind2_bucket_cachep, net, + head2, port, l3mdev, sk); + if (!tb2) + goto error; + } + /* Here we want to add a little bit of randomness to the next source * port that will be chosen. We use a max() with a random here so that * on low contention the randomness is maximal and on high contention @@ -798,7 +1030,10 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, WRITE_ONCE(table_perturb[index], READ_ONCE(table_perturb[index]) + i + 2); /* Head lock still held and bh's disabled */ - inet_bind_hash(sk, tb, port); + inet_bind_hash(sk, tb, tb2, port); + + spin_unlock(&head2->lock); + if (sk_unhashed(sk)) { inet_sk(sk)->inet_sport = htons(port); inet_ehash_nolisten(sk, (struct sock *)tw, NULL); @@ -810,6 +1045,13 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, inet_twsk_deschedule_put(tw); local_bh_enable(); return 0; + +error: + spin_unlock(&head2->lock); + if (tb_created) + inet_bind_bucket_destroy(hinfo->bind_bucket_cachep, tb); + spin_unlock_bh(&head->lock); + return -ENOMEM; } /* diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index ba2bdc811374..423470115088 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4690,6 +4690,12 @@ void __init tcp_init(void) SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT, NULL); + tcp_hashinfo.bind2_bucket_cachep = + kmem_cache_create("tcp_bind2_bucket", + sizeof(struct inet_bind2_bucket), 0, + SLAB_HWCACHE_ALIGN | SLAB_PANIC | + SLAB_ACCOUNT, + NULL); /* Size and allocate the main established and bind bucket * hash tables. @@ -4713,7 +4719,7 @@ void __init tcp_init(void) panic("TCP: failed to alloc ehash_locks"); tcp_hashinfo.bhash = alloc_large_system_hash("TCP bind", - sizeof(struct inet_bind_hashbucket), + 2 * sizeof(struct inet_bind_hashbucket), tcp_hashinfo.ehash_mask + 1, 17, /* one slot per 128 KB of memory */ 0, @@ -4722,9 +4728,12 @@ void __init tcp_init(void) 0, 64 * 1024); tcp_hashinfo.bhash_size = 1U << tcp_hashinfo.bhash_size; + tcp_hashinfo.bhash2 = tcp_hashinfo.bhash + tcp_hashinfo.bhash_size; for (i = 0; i < tcp_hashinfo.bhash_size; i++) { spin_lock_init(&tcp_hashinfo.bhash[i].lock); INIT_HLIST_HEAD(&tcp_hashinfo.bhash[i].chain); + spin_lock_init(&tcp_hashinfo.bhash2[i].lock); + INIT_HLIST_HEAD(&tcp_hashinfo.bhash2[i].chain); } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index c7e7101647dc..3b6a4bd6898e 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -199,11 +199,13 @@ static int tcp_v4_pre_connect(struct sock *sk, struct sockaddr *uaddr, /* This will initiate an outgoing connection. */ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { + struct inet_bind_hashbucket *prev_addr_hashbucket = NULL; struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; + __be32 daddr, nexthop, prev_sk_rcv_saddr; struct inet_sock *inet = inet_sk(sk); struct tcp_sock *tp = tcp_sk(sk); __be16 orig_sport, orig_dport; - __be32 daddr, nexthop; + bool new_sk_saddr = false; struct flowi4 *fl4; struct rtable *rt; int err; @@ -246,10 +248,28 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) if (!inet_opt || !inet_opt->opt.srr) daddr = fl4->daddr; - if (!inet->inet_saddr) + if (!inet->inet_saddr) { + if (inet_csk(sk)->icsk_bind2_hash) + prev_addr_hashbucket = inet_bhashfn_portaddr(&tcp_hashinfo, + sk, sock_net(sk), + inet->inet_num); + prev_sk_rcv_saddr = sk->sk_rcv_saddr; inet->inet_saddr = fl4->saddr; + new_sk_saddr = true; + } + sk_rcv_saddr_set(sk, inet->inet_saddr); + if (new_sk_saddr) { + err = inet_bhash2_update_saddr(prev_addr_hashbucket, sk); + if (err) { + inet->inet_saddr = 0; + sk_rcv_saddr_set(sk, prev_sk_rcv_saddr); + ip_rt_put(rt); + return err; + } + } + if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) { /* Reset inherited state */ tp->rx_opt.ts_recent = 0; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 85b8b765dcb1..4573d6a30ea6 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -287,8 +287,21 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, } if (!saddr) { + struct inet_bind_hashbucket *prev_addr_hashbucket = NULL; + struct in6_addr prev_v6_rcv_saddr = sk->sk_v6_rcv_saddr; + + if (icsk->icsk_bind2_hash) + prev_addr_hashbucket = inet_bhashfn_portaddr(&tcp_hashinfo, + sk, sock_net(sk), + inet->inet_num); saddr = &fl6.saddr; sk->sk_v6_rcv_saddr = *saddr; + + err = inet_bhash2_update_saddr(prev_addr_hashbucket, sk); + if (err) { + sk->sk_v6_rcv_saddr = prev_v6_rcv_saddr; + goto failure; + } } /* set the source address */ From patchwork Fri Jul 22 19:54:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joanne Koong X-Patchwork-Id: 12926822 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EBB68C433EF for ; Fri, 22 Jul 2022 19:57:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231149AbiGVT5O (ORCPT ); Fri, 22 Jul 2022 15:57:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52942 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236459AbiGVT5N (ORCPT ); Fri, 22 Jul 2022 15:57:13 -0400 Received: from 66-220-155-178.mail-mxout.facebook.com (66-220-155-178.mail-mxout.facebook.com [66.220.155.178]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 73C0B9E2AA for ; Fri, 22 Jul 2022 12:57:12 -0700 (PDT) Received: by devbig010.atn6.facebook.com (Postfix, from userid 115148) id 8C8D8F53C553; Fri, 22 Jul 2022 12:56:59 -0700 (PDT) From: Joanne Koong To: netdev@vger.kernel.org Cc: pabeni@redhat.com, edumazet@google.com, kuba@kernel.org, kafai@fb.com, davem@davemloft.net, Joanne Koong Subject: [PATCH net-next v3 2/3] selftests/net: Add test for timing a bind request to a port with a populated bhash entry Date: Fri, 22 Jul 2022 12:54:05 -0700 Message-Id: <20220722195406.1304948-3-joannelkoong@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220722195406.1304948-1-joannelkoong@gmail.com> References: <20220722195406.1304948-1-joannelkoong@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org This test populates the bhash table for a given port with MAX_THREADS * MAX_CONNECTIONS sockets, and then times how long a bind request on the port takes. When populating the bhash table, we create the sockets and then bind the sockets to the same address and port (SO_REUSEADDR and SO_REUSEPORT are set). When timing how long a bind on the port takes, we bind on a different address without SO_REUSEPORT set. We do not set SO_REUSEPORT because we are interested in the case where the bind request does not go through the tb->fastreuseport path, which is fragile (eg tb->fastreuseport path does not work if binding with a different uid). To run the script: Usage: ./bind_bhash.sh [-6 | -4] [-p port] [-a address] 6: use ipv6 4: use ipv4 port: Port number address: ip address Without any arguments, ./bind_bhash.sh defaults to ipv6 using ip address "2001:0db8:0:f101::1" on port 443. On my local machine, I see: ipv4: before - 0.002317 seconds with bhash2 - 0.000020 seconds ipv6: before - 0.002431 seconds with bhash2 - 0.000021 seconds Signed-off-by: Joanne Koong --- tools/testing/selftests/net/.gitignore | 3 +- tools/testing/selftests/net/Makefile | 3 + tools/testing/selftests/net/bind_bhash.c | 144 ++++++++++++++++++++++ tools/testing/selftests/net/bind_bhash.sh | 66 ++++++++++ 4 files changed, 215 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/net/bind_bhash.c create mode 100755 tools/testing/selftests/net/bind_bhash.sh diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore index 892306bdb47d..04c4c4152970 100644 --- a/tools/testing/selftests/net/.gitignore +++ b/tools/testing/selftests/net/.gitignore @@ -38,4 +38,5 @@ ioam6_parser toeplitz tun cmsg_sender -unix_connect \ No newline at end of file +unix_connect +bind_bhash diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index 80628bf8413a..6b621bcbcb8e 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -40,6 +40,7 @@ TEST_PROGS += arp_ndisc_evict_nocarrier.sh TEST_PROGS += ndisc_unsolicited_na_test.sh TEST_PROGS += arp_ndisc_untracked_subnets.sh TEST_PROGS += stress_reuseport_listen.sh +TEST_PROGS += bind_bhash.sh TEST_PROGS_EXTENDED := in_netns.sh setup_loopback.sh setup_veth.sh TEST_PROGS_EXTENDED += toeplitz_client.sh toeplitz.sh TEST_GEN_FILES = socket nettest @@ -60,6 +61,7 @@ TEST_GEN_FILES += toeplitz TEST_GEN_FILES += cmsg_sender TEST_GEN_FILES += stress_reuseport_listen TEST_PROGS += test_vxlan_vnifiltering.sh +TEST_GEN_FILES += bind_bhash TEST_FILES := settings @@ -71,3 +73,4 @@ include bpf/Makefile $(OUTPUT)/reuseport_bpf_numa: LDLIBS += -lnuma $(OUTPUT)/tcp_mmap: LDLIBS += -lpthread $(OUTPUT)/tcp_inq: LDLIBS += -lpthread +$(OUTPUT)/bind_bhash: LDLIBS += -lpthread diff --git a/tools/testing/selftests/net/bind_bhash.c b/tools/testing/selftests/net/bind_bhash.c new file mode 100644 index 000000000000..57ff67a3751e --- /dev/null +++ b/tools/testing/selftests/net/bind_bhash.c @@ -0,0 +1,144 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This times how long it takes to bind to a port when the port already + * has multiple sockets in its bhash table. + * + * In the setup(), we populate the port's bhash table with + * MAX_THREADS * MAX_CONNECTIONS number of entries. + */ + +#include +#include +#include +#include +#include +#include + +#define MAX_THREADS 600 +#define MAX_CONNECTIONS 40 + +static const char *setup_addr_v6 = "::1"; +static const char *setup_addr_v4 = "127.0.0.1"; +static const char *setup_addr; +static const char *bind_addr; +static const char *port; +bool use_v6; +int ret; + +static int fd_array[MAX_THREADS][MAX_CONNECTIONS]; + +static int bind_socket(int opt, const char *addr) +{ + struct addrinfo *res, hint = {}; + int sock_fd, reuse = 1, err; + int domain = use_v6 ? AF_INET6 : AF_INET; + + sock_fd = socket(domain, SOCK_STREAM, 0); + if (sock_fd < 0) { + perror("socket fd err"); + return sock_fd; + } + + hint.ai_family = domain; + hint.ai_socktype = SOCK_STREAM; + + err = getaddrinfo(addr, port, &hint, &res); + if (err) { + perror("getaddrinfo failed"); + goto cleanup; + } + + if (opt) { + err = setsockopt(sock_fd, SOL_SOCKET, opt, &reuse, sizeof(reuse)); + if (err) { + perror("setsockopt failed"); + goto cleanup; + } + } + + err = bind(sock_fd, res->ai_addr, res->ai_addrlen); + if (err) { + perror("failed to bind to port"); + goto cleanup; + } + + return sock_fd; + +cleanup: + close(sock_fd); + return err; +} + +static void *setup(void *arg) +{ + int sock_fd, i; + int *array = (int *)arg; + + for (i = 0; i < MAX_CONNECTIONS; i++) { + sock_fd = bind_socket(SO_REUSEADDR | SO_REUSEPORT, setup_addr); + if (sock_fd < 0) { + ret = sock_fd; + pthread_exit(&ret); + } + array[i] = sock_fd; + } + + return NULL; +} + +int main(int argc, const char *argv[]) +{ + int listener_fd, sock_fd, i, j; + pthread_t tid[MAX_THREADS]; + clock_t begin, end; + + if (argc != 4) { + printf("Usage: listener \n"); + return -1; + } + + port = argv[1]; + use_v6 = strcmp(argv[2], "ipv6") == 0; + bind_addr = argv[3]; + + setup_addr = use_v6 ? setup_addr_v6 : setup_addr_v4; + + listener_fd = bind_socket(SO_REUSEADDR | SO_REUSEPORT, setup_addr); + if (listen(listener_fd, 100) < 0) { + perror("listen failed"); + return -1; + } + + /* Set up threads to populate the bhash table entry for the port */ + for (i = 0; i < MAX_THREADS; i++) + pthread_create(&tid[i], NULL, setup, fd_array[i]); + + for (i = 0; i < MAX_THREADS; i++) + pthread_join(tid[i], NULL); + + if (ret) + goto done; + + begin = clock(); + + /* Bind to the same port on a different address */ + sock_fd = bind_socket(0, bind_addr); + if (sock_fd < 0) + goto done; + + end = clock(); + + printf("time spent = %f\n", (double)(end - begin) / CLOCKS_PER_SEC); + + /* clean up */ + close(sock_fd); + +done: + close(listener_fd); + for (i = 0; i < MAX_THREADS; i++) { + for (j = 0; i < MAX_THREADS; i++) + close(fd_array[i][j]); + } + + return 0; +} diff --git a/tools/testing/selftests/net/bind_bhash.sh b/tools/testing/selftests/net/bind_bhash.sh new file mode 100755 index 000000000000..ca0292d4b441 --- /dev/null +++ b/tools/testing/selftests/net/bind_bhash.sh @@ -0,0 +1,66 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +NR_FILES=32768 +SAVED_NR_FILES=$(ulimit -n) + +# default values +port=443 +addr_v6="2001:0db8:0:f101::1" +addr_v4="10.8.8.8" +use_v6=true +addr="" + +usage() { + echo "Usage: $0 [-6 | -4] [-p port] [-a address]" + echo -e "\t6: use ipv6" + echo -e "\t4: use ipv4" + echo -e "\tport: Port number" + echo -e "\taddress: ip address" +} + +while getopts "ha:p:64" opt; do + case ${opt} in + h) + usage $0 + exit 0 + ;; + a) addr=$OPTARG;; + p) + port=$OPTARG;; + 6) + use_v6=true;; + 4) + use_v6=false;; + esac +done + +setup() { + if [[ "$use_v6" == true ]]; then + ip addr add $addr_v6 nodad dev eth0 + else + ip addr add $addr_v4 dev lo + fi + ulimit -n $NR_FILES +} + +cleanup() { + if [[ "$use_v6" == true ]]; then + ip addr del $addr_v6 dev eth0 + else + ip addr del $addr_v4/32 dev lo + fi + ulimit -n $SAVED_NR_FILES +} + +if [[ "$addr" != "" ]]; then + addr_v4=$addr; + addr_v6=$addr; +fi +setup +if [[ "$use_v6" == true ]] ; then + ./bind_bhash $port "ipv6" $addr_v6 +else + ./bind_bhash $port "ipv4" $addr_v4 +fi +cleanup From patchwork Fri Jul 22 19:54:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joanne Koong X-Patchwork-Id: 12926823 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 437E4C43334 for ; Fri, 22 Jul 2022 19:57:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233737AbiGVT5S (ORCPT ); Fri, 22 Jul 2022 15:57:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232071AbiGVT5P (ORCPT ); Fri, 22 Jul 2022 15:57:15 -0400 Received: from 66-220-155-178.mail-mxout.facebook.com (66-220-155-178.mail-mxout.facebook.com [66.220.155.178]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E3A59C27B for ; Fri, 22 Jul 2022 12:57:14 -0700 (PDT) Received: by devbig010.atn6.facebook.com (Postfix, from userid 115148) id 7427BF53C555; Fri, 22 Jul 2022 12:57:00 -0700 (PDT) From: Joanne Koong To: netdev@vger.kernel.org Cc: pabeni@redhat.com, edumazet@google.com, kuba@kernel.org, kafai@fb.com, davem@davemloft.net, Joanne Koong Subject: [PATCH net-next v3 3/3] selftests/net: Add sk_bind_sendto_listen and sk_connect_zero_addr Date: Fri, 22 Jul 2022 12:54:06 -0700 Message-Id: <20220722195406.1304948-4-joannelkoong@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220722195406.1304948-1-joannelkoong@gmail.com> References: <20220722195406.1304948-1-joannelkoong@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org This patch adds 2 new tests: sk_bind_sendto_listen and sk_connect_zero_addr. The sk_bind_sendto_listen test exercises the path where a socket's rcv saddr changes after it has been added to the binding tables, and then a listen() on the socket is invoked. The listen() should succeed. The sk_bind_sendto_listen test is copied over from one of syzbot's tests: https://syzkaller.appspot.com/x/repro.c?x=1673a38df00000 The sk_connect_zero_addr test exercises the path where the socket was never previously added to the binding tables and it gets assigned a saddr upon a connect() to address 0. Signed-off-by: Joanne Koong --- tools/testing/selftests/net/.gitignore | 2 + tools/testing/selftests/net/Makefile | 2 + .../selftests/net/sk_bind_sendto_listen.c | 80 +++++++++++++++++++ .../selftests/net/sk_connect_zero_addr.c | 57 +++++++++++++ 4 files changed, 141 insertions(+) create mode 100644 tools/testing/selftests/net/sk_bind_sendto_listen.c create mode 100644 tools/testing/selftests/net/sk_connect_zero_addr.c diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore index 04c4c4152970..7e1d358929a6 100644 --- a/tools/testing/selftests/net/.gitignore +++ b/tools/testing/selftests/net/.gitignore @@ -40,3 +40,5 @@ tun cmsg_sender unix_connect bind_bhash +sk_bind_sendto_listen +sk_connect_zero_addr diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index 6b621bcbcb8e..a4d9d4ab456d 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -62,6 +62,8 @@ TEST_GEN_FILES += cmsg_sender TEST_GEN_FILES += stress_reuseport_listen TEST_PROGS += test_vxlan_vnifiltering.sh TEST_GEN_FILES += bind_bhash +TEST_GEN_PROGS += sk_bind_sendto_listen +TEST_GEN_PROGS += sk_connect_zero_addr TEST_FILES := settings diff --git a/tools/testing/selftests/net/sk_bind_sendto_listen.c b/tools/testing/selftests/net/sk_bind_sendto_listen.c new file mode 100644 index 000000000000..b420d830f72c --- /dev/null +++ b/tools/testing/selftests/net/sk_bind_sendto_listen.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include + +int main(void) +{ + int fd1, fd2, one = 1; + struct sockaddr_in6 bind_addr = { + .sin6_family = AF_INET6, + .sin6_port = htons(20000), + .sin6_flowinfo = htonl(0), + .sin6_addr = {}, + .sin6_scope_id = 0, + }; + + inet_pton(AF_INET6, "::", &bind_addr.sin6_addr); + + fd1 = socket(AF_INET6, SOCK_STREAM, IPPROTO_IP); + if (fd1 < 0) { + error(1, errno, "socket fd1"); + return -1; + } + + if (setsockopt(fd1, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) { + error(1, errno, "setsockopt(SO_REUSEADDR) fd1"); + goto out_err1; + } + + if (bind(fd1, (struct sockaddr *)&bind_addr, sizeof(bind_addr))) { + error(1, errno, "bind fd1"); + goto out_err1; + } + + if (sendto(fd1, NULL, 0, MSG_FASTOPEN, (struct sockaddr *)&bind_addr, + sizeof(bind_addr))) { + error(1, errno, "sendto fd1"); + goto out_err1; + } + + fd2 = socket(AF_INET6, SOCK_STREAM, IPPROTO_IP); + if (fd2 < 0) { + error(1, errno, "socket fd2"); + goto out_err1; + } + + if (setsockopt(fd2, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) { + error(1, errno, "setsockopt(SO_REUSEADDR) fd2"); + goto out_err2; + } + + if (bind(fd2, (struct sockaddr *)&bind_addr, sizeof(bind_addr))) { + error(1, errno, "bind fd2"); + goto out_err2; + } + + if (sendto(fd2, NULL, 0, MSG_FASTOPEN, (struct sockaddr *)&bind_addr, + sizeof(bind_addr)) != -1) { + error(1, errno, "sendto fd2"); + goto out_err2; + } + + if (listen(fd2, 0)) { + error(1, errno, "listen"); + goto out_err2; + } + + close(fd2); + close(fd1); + return 0; + +out_err2: + close(fd2); + +out_err1: + close(fd1); + return -1; +} diff --git a/tools/testing/selftests/net/sk_connect_zero_addr.c b/tools/testing/selftests/net/sk_connect_zero_addr.c new file mode 100644 index 000000000000..7857da5ac3f8 --- /dev/null +++ b/tools/testing/selftests/net/sk_connect_zero_addr.c @@ -0,0 +1,57 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include + +int main(void) +{ + int fd1, fd2; + struct sockaddr_in6 bind_addr = { + .sin6_family = AF_INET6, + .sin6_port = htons(20000), + .sin6_flowinfo = htonl(0), + .sin6_addr = {}, + .sin6_scope_id = 0, + }; + + inet_pton(AF_INET6, "::", &bind_addr.sin6_addr); + + fd1 = socket(AF_INET6, SOCK_STREAM, IPPROTO_IP); + if (fd1 < 0) { + error(1, errno, "socket fd1"); + return -1; + } + + if (bind(fd1, (struct sockaddr *)&bind_addr, sizeof(bind_addr))) { + error(1, errno, "bind fd1"); + goto out_err1; + } + + if (listen(fd1, 0)) { + error(1, errno, "listen"); + goto out_err1; + } + + fd2 = socket(AF_INET6, SOCK_STREAM, IPPROTO_IP); + if (fd2 < 0) { + error(1, errno, "socket fd2"); + goto out_err1; + } + + if (connect(fd2, (struct sockaddr *)&bind_addr, sizeof(bind_addr))) { + error(1, errno, "bind fd2"); + goto out_err2; + } + + close(fd2); + close(fd1); + return 0; + +out_err2: + close(fd2); +out_err1: + close(fd1); + return -1; +}