diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h index ee88f0f1350f..c2b15f7e5516 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 e9cf2157ed8a..44a419b9e3d5 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 */ @@ -182,14 +211,61 @@ 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 d08cfe190a78..ca469980e006 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 { @@ -870,6 +872,16 @@ 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) \ @@ -887,6 +899,8 @@ 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..6a6e121dc00c 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -45,10 +45,11 @@ 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; struct flowi4 *fl4; struct rtable *rt; int err; @@ -89,9 +90,29 @@ 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; + } + sk_rcv_saddr_set(sk, inet->inet_saddr); + + if (prev_addr_hashbucket) { + 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..e57b43006074 100644 --- a/net/dccp/ipv6.c +++ b/net/dccp/ipv6.c @@ -934,8 +934,26 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr, } if (saddr == NULL) { + struct inet_bind_hashbucket *prev_addr_hashbucket = NULL; + struct in6_addr prev_v6_rcv_saddr; + + if (icsk->icsk_bind2_hash) { + prev_addr_hashbucket = inet_bhashfn_portaddr(&dccp_hashinfo, + sk, sock_net(sk), + inet->inet_num); + prev_v6_rcv_saddr = sk->sk_v6_rcv_saddr; + } + saddr = &fl6.saddr; sk->sk_v6_rcv_saddr = *saddr; + + if (prev_addr_hashbucket) { + 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 e13641c65f88..7cd4a6cc99fc 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..2e6a3cb06815 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; 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 +1242,34 @@ 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; + } + + 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 int inet_csk_bind_conflict(const struct sock *sk, - const struct inet_bind_bucket *tb, - bool relax, bool reuseport_ok) +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) +{ 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; } - return sk2 != NULL; + + /* 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; + } + + 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; - if (!tb) - goto tb_not_found; - goto success; - } - 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)) + head2_lock_acquired = true; + + if (tb && tb2) goto success; - if (inet_csk_bind_conflict(sk, tb, true, true)) + 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 fail_unlock; + bhash_created = 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 } } -void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb, - const unsigned short snum) +bool inet_bind_bucket_match(const struct inet_bind_bucket *tb, const struct net *net, + unsigned short port, int l3mdev) { - inet_sk(sk)->inet_num = snum; + 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, + struct inet_bind2_bucket *tb2, unsigned short port) +{ + 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 ba62f8e8bd15..baf6adb723ad 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4742,6 +4742,12 @@ 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. @@ -4765,7 +4771,7 @@ 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, @@ -4774,9 +4780,12 @@ 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 0c83780dc9bf..cc2ad67f75be 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -199,11 +199,12 @@ 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; struct flowi4 *fl4; struct rtable *rt; int err; @@ -246,10 +247,28 @@ 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; + } + sk_rcv_saddr_set(sk, inet->inet_saddr); + if (prev_addr_hashbucket) { + 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 e54eee80ce5f..ff5c4fc135fc 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -287,8 +287,25 @@ 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; + + if (icsk->icsk_bind2_hash) { + prev_addr_hashbucket = inet_bhashfn_portaddr(&tcp_hashinfo, + sk, sock_net(sk), + inet->inet_num); + prev_v6_rcv_saddr = sk->sk_v6_rcv_saddr; + } saddr = &fl6.saddr; sk->sk_v6_rcv_saddr = *saddr; + + if (prev_addr_hashbucket) { + 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 */