1 files changed, 105 insertions, 56 deletions

diff --git a/net/tipc/server.c b/net/tipc/server.c
index 8aa2a33b1e48..b8268c0882a7 100644
--- a/net/tipc/server.c
+++ b/net/tipc/server.c
@@ -2,6 +2,7 @@
  * net/tipc/server.c: TIPC server infrastructure
  *
  * Copyright (c) 2012-2013, Wind River Systems
+ * Copyright (c) 2017, Ericsson AB
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -57,12 +58,13 @@
  * @sock: socket handler associated with connection
  * @flags: indicates connection state
  * @server: pointer to connected server
+ * @sub_list: lsit to all pertaing subscriptions
+ * @sub_lock: lock protecting the subscription list
+ * @outqueue_lock: control access to the outqueue
  * @rwork: receive work item
- * @usr_data: user-specified field
  * @rx_action: what to do when connection socket is active
  * @outqueue: pointer to first outbound message in queue
  * @outqueue_lock: control access to the outqueue
- * @outqueue: list of connection objects for its server
  * @swork: send work item
  */
 struct tipc_conn {
@@ -71,9 +73,10 @@ struct tipc_conn {
 	struct socket *sock;
 	unsigned long flags;
 	struct tipc_server *server;
+	struct list_head sub_list;
+	spinlock_t sub_lock; /* for subscription list */
 	struct work_struct rwork;
 	int (*rx_action) (struct tipc_conn *con);
-	void *usr_data;
 	struct list_head outqueue;
 	spinlock_t outqueue_lock;
 	struct work_struct swork;
@@ -81,6 +84,7 @@ struct tipc_conn {
 
 /* An entry waiting to be sent */
 struct outqueue_entry {
+	u32 evt;
 	struct list_head list;
 	struct kvec iov;
 };
@@ -89,18 +93,33 @@ static void tipc_recv_work(struct work_struct *work);
 static void tipc_send_work(struct work_struct *work);
 static void tipc_clean_outqueues(struct tipc_conn *con);
 
+static bool connected(struct tipc_conn *con)
+{
+	return con && test_bit(CF_CONNECTED, &con->flags);
+}
+
+/**
+ * htohl - convert value to endianness used by destination
+ * @in: value to convert
+ * @swap: non-zero if endianness must be reversed
+ *
+ * Returns converted value
+ */
+static u32 htohl(u32 in, int swap)
+{
+	return swap ? swab32(in) : in;
+}
+
 static void tipc_conn_kref_release(struct kref *kref)
 {
 	struct tipc_conn *con = container_of(kref, struct tipc_conn, kref);
 	struct tipc_server *s = con->server;
 	struct socket *sock = con->sock;
-	struct sock *sk;
 
 	if (sock) {
-		sk = sock->sk;
 		if (test_bit(CF_SERVER, &con->flags)) {
 			__module_get(sock->ops->owner);
-			__module_get(sk->sk_prot_creator->owner);
+			__module_get(sock->sk->sk_prot_creator->owner);
 		}
 		sock_release(sock);
 		con->sock = NULL;
@@ -129,11 +148,8 @@ static struct tipc_conn *tipc_conn_lookup(struct tipc_server *s, int conid)
 
 	spin_lock_bh(&s->idr_lock);
 	con = idr_find(&s->conn_idr, conid);
-	if (con) {
-		if (!test_bit(CF_CONNECTED, &con->flags) ||
-		    !kref_get_unless_zero(&con->kref))
-			con = NULL;
-	}
+	if (!connected(con) || !kref_get_unless_zero(&con->kref))
+		con = NULL;
 	spin_unlock_bh(&s->idr_lock);
 	return con;
 }
@@ -144,7 +160,7 @@ static void sock_data_ready(struct sock *sk)
 
 	read_lock_bh(&sk->sk_callback_lock);
 	con = sock2con(sk);
-	if (con && test_bit(CF_CONNECTED, &con->flags)) {
+	if (connected(con)) {
 		conn_get(con);
 		if (!queue_work(con->server->rcv_wq, &con->rwork))
 			conn_put(con);
@@ -158,7 +174,7 @@ static void sock_write_space(struct sock *sk)
 
 	read_lock_bh(&sk->sk_callback_lock);
 	con = sock2con(sk);
-	if (con && test_bit(CF_CONNECTED, &con->flags)) {
+	if (connected(con)) {
 		conn_get(con);
 		if (!queue_work(con->server->send_wq, &con->swork))
 			conn_put(con);
@@ -181,6 +197,24 @@ static void tipc_register_callbacks(struct socket *sock, struct tipc_conn *con)
 	write_unlock_bh(&sk->sk_callback_lock);
 }
 
+/* tipc_con_delete_sub - delete a specific or all subscriptions
+ *  for a given subscriber
+ */
+static void tipc_con_delete_sub(struct tipc_conn *con, struct tipc_subscr *s)
+{
+	struct list_head *sub_list = &con->sub_list;
+	struct tipc_subscription *sub, *tmp;
+
+	spin_lock_bh(&con->sub_lock);
+	list_for_each_entry_safe(sub, tmp, sub_list, subscrp_list) {
+		if (!s || !memcmp(s, &sub->evt.s, sizeof(*s)))
+			tipc_sub_delete(sub);
+		else if (s)
+			break;
+	}
+	spin_unlock_bh(&con->sub_lock);
+}
+
 static void tipc_close_conn(struct tipc_conn *con)
 {
 	struct sock *sk = con->sock->sk;
@@ -188,10 +222,11 @@ static void tipc_close_conn(struct tipc_conn *con)
 
 	write_lock_bh(&sk->sk_callback_lock);
 	disconnect = test_and_clear_bit(CF_CONNECTED, &con->flags);
+
 	if (disconnect) {
 		sk->sk_user_data = NULL;
 		if (con->conid)
-			tipc_subscrb_delete(con->usr_data);
+			tipc_con_delete_sub(con, NULL);
 	}
 	write_unlock_bh(&sk->sk_callback_lock);
 
@@ -215,7 +250,9 @@ static struct tipc_conn *tipc_alloc_conn(struct tipc_server *s)
 
 	kref_init(&con->kref);
 	INIT_LIST_HEAD(&con->outqueue);
+	INIT_LIST_HEAD(&con->sub_list);
 	spin_lock_init(&con->outqueue_lock);
+	spin_lock_init(&con->sub_lock);
 	INIT_WORK(&con->swork, tipc_send_work);
 	INIT_WORK(&con->rwork, tipc_recv_work);
 
@@ -236,6 +273,35 @@ static struct tipc_conn *tipc_alloc_conn(struct tipc_server *s)
 	return con;
 }
 
+int tipc_con_rcv_sub(struct net *net, int conid, struct tipc_conn *con,
+		     void *buf, size_t len)
+{
+	struct tipc_subscr *s = (struct tipc_subscr *)buf;
+	struct tipc_subscription *sub;
+	bool status;
+	int swap;
+
+	/* Determine subscriber's endianness */
+	swap = !(s->filter & (TIPC_SUB_PORTS | TIPC_SUB_SERVICE |
+			      TIPC_SUB_CANCEL));
+
+	/* Detect & process a subscription cancellation request */
+	if (s->filter & htohl(TIPC_SUB_CANCEL, swap)) {
+		s->filter &= ~htohl(TIPC_SUB_CANCEL, swap);
+		tipc_con_delete_sub(con, s);
+		return 0;
+	}
+	status = !(s->filter & htohl(TIPC_SUB_NO_STATUS, swap));
+	sub = tipc_subscrp_subscribe(net, s, conid, swap, status);
+	if (!sub)
+		return -1;
+
+	spin_lock_bh(&con->sub_lock);
+	list_add(&sub->subscrp_list, &con->sub_list);
+	spin_unlock_bh(&con->sub_lock);
+	return 0;
+}
+
 static int tipc_receive_from_sock(struct tipc_conn *con)
 {
 	struct tipc_server *s = con->server;
@@ -262,9 +328,7 @@ static int tipc_receive_from_sock(struct tipc_conn *con)
 	}
 
 	read_lock_bh(&sk->sk_callback_lock);
-	if (test_bit(CF_CONNECTED, &con->flags))
-		ret = tipc_subscrb_rcv(sock_net(con->sock->sk), con->conid,
-				       con->usr_data, buf, ret);
+	ret = tipc_con_rcv_sub(s->net, con->conid, con, buf, ret);
 	read_unlock_bh(&sk->sk_callback_lock);
 	kmem_cache_free(s->rcvbuf_cache, buf);
 	if (ret < 0)
@@ -302,15 +366,6 @@ static int tipc_accept_from_sock(struct tipc_conn *con)
 	newcon->rx_action = tipc_receive_from_sock;
 	tipc_register_callbacks(newsock, newcon);
 
-	/* Notify that new connection is incoming */
-	newcon->usr_data = tipc_subscrb_create(newcon->conid);
-
-	if (!newcon->usr_data) {
-		sock_release(newsock);
-		conn_put(newcon);
-		return -ENOMEM;
-	}
-
 	/* Wake up receive process in case of 'SYN+' message */
 	newsock->sk->sk_data_ready(newsock->sk);
 	return ret;
@@ -427,7 +482,7 @@ static void tipc_clean_outqueues(struct tipc_conn *con)
 }
 
 int tipc_conn_sendmsg(struct tipc_server *s, int conid,
-		      void *data, size_t len)
+		      u32 evt, void *data, size_t len)
 {
 	struct outqueue_entry *e;
 	struct tipc_conn *con;
@@ -436,7 +491,7 @@ int tipc_conn_sendmsg(struct tipc_server *s, int conid,
 	if (!con)
 		return -EINVAL;
 
-	if (!test_bit(CF_CONNECTED, &con->flags)) {
+	if (!connected(con)) {
 		conn_put(con);
 		return 0;
 	}
@@ -446,7 +501,7 @@ int tipc_conn_sendmsg(struct tipc_server *s, int conid,
 		conn_put(con);
 		return -ENOMEM;
 	}
-
+	e->evt = evt;
 	spin_lock_bh(&con->outqueue_lock);
 	list_add_tail(&e->list, &con->outqueue);
 	spin_unlock_bh(&con->outqueue_lock);
@@ -470,10 +525,9 @@ void tipc_conn_terminate(struct tipc_server *s, int conid)
 bool tipc_topsrv_kern_subscr(struct net *net, u32 port, u32 type, u32 lower,
 			     u32 upper, u32 filter, int *conid)
 {
-	struct tipc_subscriber *scbr;
 	struct tipc_subscr sub;
-	struct tipc_server *s;
 	struct tipc_conn *con;
+	int rc;
 
 	sub.seq.type = type;
 	sub.seq.lower = lower;
@@ -487,32 +541,23 @@ bool tipc_topsrv_kern_subscr(struct net *net, u32 port, u32 type, u32 lower,
 		return false;
 
 	*conid = con->conid;
-	s = con->server;
-	scbr = tipc_subscrb_create(*conid);
-	if (!scbr) {
-		conn_put(con);
-		return false;
-	}
-
-	con->usr_data = scbr;
 	con->sock = NULL;
-	tipc_subscrb_rcv(net, *conid, scbr, &sub, sizeof(sub));
-	return true;
+	rc = tipc_con_rcv_sub(net, *conid, con, &sub, sizeof(sub));
+	if (rc < 0)
+		tipc_close_conn(con);
+	return !rc;
 }
 
 void tipc_topsrv_kern_unsubscr(struct net *net, int conid)
 {
 	struct tipc_conn *con;
-	struct tipc_server *srv;
 
 	con = tipc_conn_lookup(tipc_topsrv(net), conid);
 	if (!con)
 		return;
 
 	test_and_clear_bit(CF_CONNECTED, &con->flags);
-	srv = con->server;
-	if (con->conid)
-		tipc_subscrb_delete(con->usr_data);
+	tipc_con_delete_sub(con, NULL);
 	conn_put(con);
 	conn_put(con);
 }
@@ -537,7 +582,8 @@ static void tipc_send_kern_top_evt(struct net *net, struct tipc_event *evt)
 
 static void tipc_send_to_sock(struct tipc_conn *con)
 {
-	struct tipc_server *s = con->server;
+	struct list_head *queue = &con->outqueue;
+	struct tipc_server *srv = con->server;
 	struct outqueue_entry *e;
 	struct tipc_event *evt;
 	struct msghdr msg;
@@ -545,16 +591,20 @@ static void tipc_send_to_sock(struct tipc_conn *con)
 	int ret;
 
 	spin_lock_bh(&con->outqueue_lock);
-	while (test_bit(CF_CONNECTED, &con->flags)) {
-		e = list_entry(con->outqueue.next, struct outqueue_entry, list);
-		if ((struct list_head *) e == &con->outqueue)
-			break;
+
+	while (!list_empty(queue)) {
+		e = list_first_entry(queue, struct outqueue_entry, list);
 
 		spin_unlock_bh(&con->outqueue_lock);
 
+		if (e->evt == TIPC_SUBSCR_TIMEOUT) {
+			evt = (struct tipc_event *)e->iov.iov_base;
+			tipc_con_delete_sub(con, &evt->s);
+		}
+		memset(&msg, 0, sizeof(msg));
+		msg.msg_flags = MSG_DONTWAIT;
+
 		if (con->sock) {
-			memset(&msg, 0, sizeof(msg));
-			msg.msg_flags = MSG_DONTWAIT;
 			ret = kernel_sendmsg(con->sock, &msg, &e->iov, 1,
 					     e->iov.iov_len);
 			if (ret == -EWOULDBLOCK || ret == 0) {
@@ -565,7 +615,7 @@ static void tipc_send_to_sock(struct tipc_conn *con)
 			}
 		} else {
 			evt = e->iov.iov_base;
-			tipc_send_kern_top_evt(s->net, evt);
+			tipc_send_kern_top_evt(srv->net, evt);
 		}
 
 		/* Don't starve users filling buffers */
@@ -573,7 +623,6 @@ static void tipc_send_to_sock(struct tipc_conn *con)
 			cond_resched();
 			count = 0;
 		}
-
 		spin_lock_bh(&con->outqueue_lock);
 		list_del(&e->list);
 		tipc_free_entry(e);
@@ -591,7 +640,7 @@ static void tipc_recv_work(struct work_struct *work)
 	struct tipc_conn *con = container_of(work, struct tipc_conn, rwork);
 	int count = 0;
 
-	while (test_bit(CF_CONNECTED, &con->flags)) {
+	while (connected(con)) {
 		if (con->rx_action(con))
 			break;
 
@@ -608,7 +657,7 @@ static void tipc_send_work(struct work_struct *work)
 {
 	struct tipc_conn *con = container_of(work, struct tipc_conn, swork);
 
-	if (test_bit(CF_CONNECTED, &con->flags))
+	if (connected(con))
 		tipc_send_to_sock(con);
 
 	conn_put(con);