1 files changed, 184 insertions, 61 deletions

diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 1e5b53c2bb26..c0b7e6c21360 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -117,6 +117,32 @@ bool inet_rcv_saddr_any(const struct sock *sk)
 	return !sk->sk_rcv_saddr;
 }
 
+static bool use_bhash2_on_bind(const struct sock *sk)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	int addr_type;
+
+	if (sk->sk_family == AF_INET6) {
+		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 u32 get_bhash2_nulladdr_hash(const struct sock *sk, struct net *net,
+				    int port)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	struct in6_addr nulladdr = {};
+
+	if (sk->sk_family == AF_INET6)
+		return ipv6_portaddr_hash(net, &nulladdr, port);
+#endif
+	return ipv4_portaddr_hash(net, 0, port);
+}
+
 void inet_get_local_port_range(struct net *net, int *low, int *high)
 {
 	unsigned int seq;
@@ -130,16 +156,71 @@ 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 bind_conflict_exist(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 check_bhash2_conflict(const struct sock *sk,
+				  struct inet_bind2_bucket *tb2, kuid_t sk_uid,
+				  bool relax, bool reuseport_cb_ok,
+				  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;
+
+	sk_for_each_bound_bhash2(sk2, &tb2->owners) {
+		if (sk->sk_family == AF_INET && ipv6_only_sock(sk2))
+			continue;
+
+		if (bind_conflict_exist(sk, sk2, sk_uid, relax,
+					reuseport_cb_ok, reuseport_ok))
+			return true;
+	}
+	return false;
+}
+
+/* This should be called only when the corresponding inet_bind_bucket spinlock
+ * is held
+ */
+static int inet_csk_bind_conflict(const struct sock *sk, int port,
+				  struct inet_bind_bucket *tb,
+				  struct inet_bind2_bucket *tb2, /* may be null */
+				  bool relax, bool reuseport_ok)
+{
+	struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
 	kuid_t uid = sock_i_uid((struct sock *)sk);
+	struct sock_reuseport *reuseport_cb;
+	struct inet_bind2_hashbucket *head2;
+	bool reuseport_cb_ok;
+	struct sock *sk2;
+	struct net *net;
+	int l3mdev;
+	u32 hash;
 
 	rcu_read_lock();
 	reuseport_cb = rcu_dereference(sk->sk_reuseport_cb);
@@ -150,36 +231,42 @@ 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
 	 */
 
-	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 (!use_bhash2_on_bind(sk)) {
+		sk_for_each_bound(sk2, &tb->owners)
+			if (bind_conflict_exist(sk, sk2, uid, relax,
+						reuseport_cb_ok, reuseport_ok) &&
+			    inet_rcv_saddr_equal(sk, sk2, true))
+				return true;
+
+		return false;
 	}
-	return sk2 != NULL;
+
+	if (tb2 && check_bhash2_conflict(sk, tb2, uid, relax, reuseport_cb_ok,
+					 reuseport_ok))
+		return true;
+
+	net = sock_net(sk);
+
+	/* check there's no conflict with an existing IPV6_ADDR_ANY (if ipv6) or
+	 * INADDR_ANY (if ipv4) socket.
+	 */
+	hash = get_bhash2_nulladdr_hash(sk, net, port);
+	head2 = &hinfo->bhash2[hash & (hinfo->bhash_size - 1)];
+
+	l3mdev = inet_sk_bound_l3mdev(sk);
+	inet_bind_bucket_for_each(tb2, &head2->chain)
+		if (check_bind2_bucket_match_nulladdr(tb2, net, port, l3mdev, sk))
+			break;
+
+	if (tb2 && check_bhash2_conflict(sk, tb2, uid, relax, reuseport_cb_ok,
+					 reuseport_ok))
+		return true;
+
+	return false;
 }
 
 /*
@@ -187,16 +274,20 @@ static int inet_csk_bind_conflict(const struct sock *sk,
  * inet_bind_hashbucket lock held.
  */
 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(struct sock *sk, struct inet_bind_bucket **tb_ret,
+			struct inet_bind2_bucket **tb2_ret,
+			struct inet_bind2_hashbucket **head2_ret, int *port_ret)
 {
 	struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
-	int port = 0;
+	struct inet_bind2_hashbucket *head2;
 	struct inet_bind_hashbucket *head;
 	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;
+	bool relax = false;
+	int port = 0;
 	int l3mdev;
 
 	l3mdev = inet_sk_bound_l3mdev(sk);
@@ -235,10 +326,12 @@ other_parity_scan:
 		head = &hinfo->bhash[inet_bhashfn(net, port,
 						  hinfo->bhash_size)];
 		spin_lock_bh(&head->lock);
+		tb2 = inet_bind2_bucket_find(hinfo, net, port, l3mdev, sk,
+					     &head2);
 		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 (check_bind_bucket_match(tb, net, port, l3mdev)) {
+				if (!inet_csk_bind_conflict(sk, port, tb, tb2,
+							    relax, false))
 					goto success;
 				goto next_port;
 			}
@@ -268,6 +361,8 @@ next_port:
 success:
 	*port_ret = port;
 	*tb_ret = tb;
+	*tb2_ret = tb2;
+	*head2_ret = head2;
 	return head;
 }
 
@@ -363,54 +458,81 @@ 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;
+	bool bhash_created = false, bhash2_created = false;
+	struct inet_bind2_bucket *tb2 = NULL;
+	struct inet_bind2_hashbucket *head2;
+	struct inet_bind_bucket *tb = NULL;
 	struct inet_bind_hashbucket *head;
 	struct net *net = sock_net(sk);
-	struct inet_bind_bucket *tb = NULL;
+	int ret = 1, port = snum;
+	bool found_port = 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 && 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 (check_bind_bucket_match(tb, net, port, l3mdev))
+				break;
+
+		tb2 = inet_bind2_bucket_find(hinfo, net, port, l3mdev, sk,
+					     &head2);
+	}
+
+	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 (!tb2) {
+		tb2 = inet_bind2_bucket_create(hinfo->bind2_bucket_cachep,
+					       net, head2, port, l3mdev, sk);
+		if (!tb2)
+			goto fail_unlock;
+		bhash2_created = true;
+	}
+
+	/* If we had to find an open port, we already checked for conflicts */
+	if (!found_port && !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 (inet_csk_bind_conflict(sk, port, 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);
+	}
 	spin_unlock_bh(&head->lock);
 	return ret;
 }
@@ -957,6 +1079,7 @@ 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;