1 files changed, 231 insertions, 81 deletions

diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 62a67fdc344c..4e84ed21d16f 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);
 
@@ -150,54 +211,88 @@ 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) {
-		if (sk != sk2 &&
-		    (!sk->sk_bound_dev_if ||
-		     !sk2->sk_bound_dev_if ||
-		     sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
-			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;
-			}
-		}
+	if (!inet_use_bhash2_on_bind(sk)) {
+		struct sock *sk2;
+
+		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_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
+	int i, low, high, attempt_half, port, l3mdev;
+	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;
+	bool relax = false;
 
 	l3mdev = inet_sk_bound_l3mdev(sk);
 ports_exhausted:
@@ -219,7 +314,7 @@ other_half_scan:
 	if (likely(remaining > 1))
 		remaining &= ~1U;
 
-	offset = prandom_u32() % remaining;
+	offset = prandom_u32_max(remaining);
 	/* __inet_hash_connect() favors ports having @low parity
 	 * We do the opposite to not pollute connect() users.
 	 */
@@ -235,11 +330,20 @@ other_parity_scan:
 		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;
@@ -259,7 +363,7 @@ next_port:
 		goto other_half_scan;
 	}
 
-	if (net->ipv4.sysctl_ip_autobind_reuse && !relax) {
+	if (READ_ONCE(net->ipv4.sysctl_ip_autobind_reuse) && !relax) {
 		/* We still have a chance to connect to different destinations */
 		relax = true;
 		goto ports_exhausted;
@@ -268,6 +372,8 @@ next_port:
 success:
 	*port_ret = port;
 	*tb_ret = tb;
+	*tb2_ret = tb2;
+	*head2_ret = head2;
 	return head;
 }
 
@@ -361,56 +467,97 @@ void inet_csk_update_fastreuse(struct inet_bind_bucket *tb,
  */
 int inet_csk_get_port(struct sock *sk, unsigned short snum)
 {
+	struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 	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;
-	int l3mdev;
+	bool head2_lock_acquired = false;
+	int ret = 1, port = snum, l3mdev;
+	struct net *net = sock_net(sk);
 
 	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;
 }
@@ -759,14 +906,15 @@ static void reqsk_migrate_reset(struct request_sock *req)
 /* return true if req was found in the ehash table */
 static bool reqsk_queue_unlink(struct request_sock *req)
 {
-	struct inet_hashinfo *hashinfo = req_to_sk(req)->sk_prot->h.hashinfo;
+	struct sock *sk = req_to_sk(req);
 	bool found = false;
 
-	if (sk_hashed(req_to_sk(req))) {
+	if (sk_hashed(sk)) {
+		struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 		spinlock_t *lock = inet_ehash_lockp(hashinfo, req->rsk_hash);
 
 		spin_lock(lock);
-		found = __sk_nulls_del_node_init_rcu(req_to_sk(req));
+		found = __sk_nulls_del_node_init_rcu(sk);
 		spin_unlock(lock);
 	}
 	if (timer_pending(&req->rsk_timer) && del_timer_sync(&req->rsk_timer))
@@ -829,7 +977,8 @@ static void reqsk_timer_handler(struct timer_list *t)
 
 	icsk = inet_csk(sk_listener);
 	net = sock_net(sk_listener);
-	max_syn_ack_retries = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_synack_retries;
+	max_syn_ack_retries = icsk->icsk_syn_retries ? :
+		READ_ONCE(net->ipv4.sysctl_tcp_synack_retries);
 	/* Normally all the openreqs are young and become mature
 	 * (i.e. converted to established socket) for first timeout.
 	 * If synack was not acknowledged for 1 second, it means
@@ -866,12 +1015,9 @@ static void reqsk_timer_handler(struct timer_list *t)
 	    (!resend ||
 	     !inet_rtx_syn_ack(sk_listener, req) ||
 	     inet_rsk(req)->acked)) {
-		unsigned long timeo;
-
 		if (req->num_timeout++ == 0)
 			atomic_dec(&queue->young);
-		timeo = min(TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX);
-		mod_timer(&req->rsk_timer, jiffies + timeo);
+		mod_timer(&req->rsk_timer, jiffies + reqsk_timeout(req, TCP_RTO_MAX));
 
 		if (!nreq)
 			return;
@@ -960,6 +1106,7 @@ 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;
@@ -1035,7 +1182,7 @@ void inet_csk_prepare_forced_close(struct sock *sk)
 }
 EXPORT_SYMBOL(inet_csk_prepare_forced_close);
 
-int inet_csk_listen_start(struct sock *sk, int backlog)
+int inet_csk_listen_start(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct inet_sock *inet = inet_sk(sk);
@@ -1046,6 +1193,9 @@ int inet_csk_listen_start(struct sock *sk, int backlog)
 	sk->sk_ack_backlog = 0;
 	inet_csk_delack_init(sk);
 
+	if (sk->sk_txrehash == SOCK_TXREHASH_DEFAULT)
+		sk->sk_txrehash = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
+
 	/* There is race window here: we announce ourselves listening,
 	 * but this transition is still not validated by get_port().
 	 * It is OK, because this socket enters to hash table only