v4.19.13 snapshot.
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
new file mode 100644
index 0000000..3d7c746
--- /dev/null
+++ b/net/ipv6/inet6_hashtables.c
@@ -0,0 +1,346 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * Generic INET6 transport hashtables
+ *
+ * Authors: Lotsa people, from code originally in tcp, generalised here
+ * by Arnaldo Carvalho de Melo <acme@mandriva.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/random.h>
+
+#include <net/addrconf.h>
+#include <net/inet_connection_sock.h>
+#include <net/inet_hashtables.h>
+#include <net/inet6_hashtables.h>
+#include <net/secure_seq.h>
+#include <net/ip.h>
+#include <net/sock_reuseport.h>
+
+u32 inet6_ehashfn(const struct net *net,
+ const struct in6_addr *laddr, const u16 lport,
+ const struct in6_addr *faddr, const __be16 fport)
+{
+ static u32 inet6_ehash_secret __read_mostly;
+ static u32 ipv6_hash_secret __read_mostly;
+
+ u32 lhash, fhash;
+
+ net_get_random_once(&inet6_ehash_secret, sizeof(inet6_ehash_secret));
+ net_get_random_once(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
+
+ lhash = (__force u32)laddr->s6_addr32[3];
+ fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret);
+
+ return __inet6_ehashfn(lhash, lport, fhash, fport,
+ inet6_ehash_secret + net_hash_mix(net));
+}
+
+/*
+ * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
+ * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
+ *
+ * The sockhash lock must be held as a reader here.
+ */
+struct sock *__inet6_lookup_established(struct net *net,
+ struct inet_hashinfo *hashinfo,
+ const struct in6_addr *saddr,
+ const __be16 sport,
+ const struct in6_addr *daddr,
+ const u16 hnum,
+ const int dif, const int sdif)
+{
+ struct sock *sk;
+ const struct hlist_nulls_node *node;
+ const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
+ /* Optimize here for direct hit, only listening connections can
+ * have wildcards anyways.
+ */
+ unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
+ unsigned int slot = hash & hashinfo->ehash_mask;
+ struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
+
+
+begin:
+ sk_nulls_for_each_rcu(sk, node, &head->chain) {
+ if (sk->sk_hash != hash)
+ continue;
+ if (!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))
+ continue;
+ if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
+ goto out;
+
+ if (unlikely(!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))) {
+ sock_gen_put(sk);
+ goto begin;
+ }
+ goto found;
+ }
+ if (get_nulls_value(node) != slot)
+ goto begin;
+out:
+ sk = NULL;
+found:
+ return sk;
+}
+EXPORT_SYMBOL(__inet6_lookup_established);
+
+static inline int compute_score(struct sock *sk, struct net *net,
+ const unsigned short hnum,
+ const struct in6_addr *daddr,
+ const int dif, const int sdif, bool exact_dif)
+{
+ int score = -1;
+
+ if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum &&
+ sk->sk_family == PF_INET6) {
+
+ score = 1;
+ if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
+ if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
+ return -1;
+ score++;
+ }
+ if (sk->sk_bound_dev_if || exact_dif) {
+ bool dev_match = (sk->sk_bound_dev_if == dif ||
+ sk->sk_bound_dev_if == sdif);
+
+ if (!dev_match)
+ return -1;
+ if (sk->sk_bound_dev_if)
+ score++;
+ }
+ if (sk->sk_incoming_cpu == raw_smp_processor_id())
+ score++;
+ }
+ return score;
+}
+
+/* called with rcu_read_lock() */
+static struct sock *inet6_lhash2_lookup(struct net *net,
+ struct inet_listen_hashbucket *ilb2,
+ struct sk_buff *skb, int doff,
+ const struct in6_addr *saddr,
+ const __be16 sport, const struct in6_addr *daddr,
+ const unsigned short hnum, const int dif, const int sdif)
+{
+ bool exact_dif = inet6_exact_dif_match(net, skb);
+ struct inet_connection_sock *icsk;
+ struct sock *sk, *result = NULL;
+ int score, hiscore = 0;
+ u32 phash = 0;
+
+ inet_lhash2_for_each_icsk_rcu(icsk, &ilb2->head) {
+ sk = (struct sock *)icsk;
+ score = compute_score(sk, net, hnum, daddr, dif, sdif,
+ exact_dif);
+ if (score > hiscore) {
+ if (sk->sk_reuseport) {
+ phash = inet6_ehashfn(net, daddr, hnum,
+ saddr, sport);
+ result = reuseport_select_sock(sk, phash,
+ skb, doff);
+ if (result)
+ return result;
+ }
+ result = sk;
+ hiscore = score;
+ }
+ }
+
+ return result;
+}
+
+struct sock *inet6_lookup_listener(struct net *net,
+ struct inet_hashinfo *hashinfo,
+ struct sk_buff *skb, int doff,
+ const struct in6_addr *saddr,
+ const __be16 sport, const struct in6_addr *daddr,
+ const unsigned short hnum, const int dif, const int sdif)
+{
+ unsigned int hash = inet_lhashfn(net, hnum);
+ struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash];
+ bool exact_dif = inet6_exact_dif_match(net, skb);
+ struct inet_listen_hashbucket *ilb2;
+ struct sock *sk, *result = NULL;
+ int score, hiscore = 0;
+ unsigned int hash2;
+ u32 phash = 0;
+
+ if (ilb->count <= 10 || !hashinfo->lhash2)
+ goto port_lookup;
+
+ /* Too many sk in the ilb bucket (which is hashed by port alone).
+ * Try lhash2 (which is hashed by port and addr) instead.
+ */
+
+ hash2 = ipv6_portaddr_hash(net, daddr, hnum);
+ ilb2 = inet_lhash2_bucket(hashinfo, hash2);
+ if (ilb2->count > ilb->count)
+ goto port_lookup;
+
+ result = inet6_lhash2_lookup(net, ilb2, skb, doff,
+ saddr, sport, daddr, hnum,
+ dif, sdif);
+ if (result)
+ goto done;
+
+ /* Lookup lhash2 with in6addr_any */
+
+ hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
+ ilb2 = inet_lhash2_bucket(hashinfo, hash2);
+ if (ilb2->count > ilb->count)
+ goto port_lookup;
+
+ result = inet6_lhash2_lookup(net, ilb2, skb, doff,
+ saddr, sport, daddr, hnum,
+ dif, sdif);
+ goto done;
+
+port_lookup:
+ sk_for_each(sk, &ilb->head) {
+ score = compute_score(sk, net, hnum, daddr, dif, sdif, exact_dif);
+ if (score > hiscore) {
+ if (sk->sk_reuseport) {
+ phash = inet6_ehashfn(net, daddr, hnum,
+ saddr, sport);
+ result = reuseport_select_sock(sk, phash,
+ skb, doff);
+ if (result)
+ goto done;
+ }
+ result = sk;
+ hiscore = score;
+ }
+ }
+done:
+ if (unlikely(IS_ERR(result)))
+ return NULL;
+ return result;
+}
+EXPORT_SYMBOL_GPL(inet6_lookup_listener);
+
+struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
+ struct sk_buff *skb, int doff,
+ const struct in6_addr *saddr, const __be16 sport,
+ const struct in6_addr *daddr, const __be16 dport,
+ const int dif)
+{
+ struct sock *sk;
+ bool refcounted;
+
+ sk = __inet6_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
+ ntohs(dport), dif, 0, &refcounted);
+ if (sk && !refcounted && !refcount_inc_not_zero(&sk->sk_refcnt))
+ sk = NULL;
+ return sk;
+}
+EXPORT_SYMBOL_GPL(inet6_lookup);
+
+static int __inet6_check_established(struct inet_timewait_death_row *death_row,
+ struct sock *sk, const __u16 lport,
+ struct inet_timewait_sock **twp)
+{
+ struct inet_hashinfo *hinfo = death_row->hashinfo;
+ struct inet_sock *inet = inet_sk(sk);
+ const struct in6_addr *daddr = &sk->sk_v6_rcv_saddr;
+ const struct in6_addr *saddr = &sk->sk_v6_daddr;
+ const int dif = sk->sk_bound_dev_if;
+ struct net *net = sock_net(sk);
+ const int sdif = l3mdev_master_ifindex_by_index(net, dif);
+ const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
+ const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
+ inet->inet_dport);
+ struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
+ spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
+ struct sock *sk2;
+ const struct hlist_nulls_node *node;
+ struct inet_timewait_sock *tw = NULL;
+
+ spin_lock(lock);
+
+ sk_nulls_for_each(sk2, node, &head->chain) {
+ if (sk2->sk_hash != hash)
+ continue;
+
+ if (likely(INET6_MATCH(sk2, net, saddr, daddr, ports,
+ dif, sdif))) {
+ if (sk2->sk_state == TCP_TIME_WAIT) {
+ tw = inet_twsk(sk2);
+ if (twsk_unique(sk, sk2, twp))
+ break;
+ }
+ goto not_unique;
+ }
+ }
+
+ /* Must record num and sport now. Otherwise we will see
+ * in hash table socket with a funny identity.
+ */
+ inet->inet_num = lport;
+ inet->inet_sport = htons(lport);
+ sk->sk_hash = hash;
+ WARN_ON(!sk_unhashed(sk));
+ __sk_nulls_add_node_rcu(sk, &head->chain);
+ if (tw) {
+ sk_nulls_del_node_init_rcu((struct sock *)tw);
+ __NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
+ }
+ spin_unlock(lock);
+ sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
+
+ if (twp) {
+ *twp = tw;
+ } else if (tw) {
+ /* Silly. Should hash-dance instead... */
+ inet_twsk_deschedule_put(tw);
+ }
+ return 0;
+
+not_unique:
+ spin_unlock(lock);
+ return -EADDRNOTAVAIL;
+}
+
+static u32 inet6_sk_port_offset(const struct sock *sk)
+{
+ const struct inet_sock *inet = inet_sk(sk);
+
+ return secure_ipv6_port_ephemeral(sk->sk_v6_rcv_saddr.s6_addr32,
+ sk->sk_v6_daddr.s6_addr32,
+ inet->inet_dport);
+}
+
+int inet6_hash_connect(struct inet_timewait_death_row *death_row,
+ struct sock *sk)
+{
+ u32 port_offset = 0;
+
+ if (!inet_sk(sk)->inet_num)
+ port_offset = inet6_sk_port_offset(sk);
+ return __inet_hash_connect(death_row, sk, port_offset,
+ __inet6_check_established);
+}
+EXPORT_SYMBOL_GPL(inet6_hash_connect);
+
+int inet6_hash(struct sock *sk)
+{
+ int err = 0;
+
+ if (sk->sk_state != TCP_CLOSE) {
+ local_bh_disable();
+ err = __inet_hash(sk, NULL);
+ local_bh_enable();
+ }
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(inet6_hash);