Fix: reception buffer of control connection is leaked

[lttng-tools.git] / src / bin / lttng-relayd / connection.c

diff --git a/src/bin/lttng-relayd/connection.c b/src/bin/lttng-relayd/connection.c
index f3d7e642ef2aa0139bce4a1f927d8a3ee56f1f77..cf93fb6e7ba93df52b548ace622c2387eea43c97 100644 (file)
--- a/src/bin/lttng-relayd/connection.c
+++ b/src/bin/lttng-relayd/connection.c
@@ -27,16 +27,7 @@
 
 bool connection_get(struct relay_connection *conn)
 {
-       bool has_ref = false;
-
-       pthread_mutex_lock(&conn->reflock);
-       if (conn->ref.refcount != 0) {
-               has_ref = true;
-               urcu_ref_get(&conn->ref);
-       }
-       pthread_mutex_unlock(&conn->reflock);
-
-       return has_ref;
+       return urcu_ref_get_unless_zero(&conn->ref);
 }
 
 struct relay_connection *connection_get_by_sock(struct lttng_ht *relay_connections_ht,
@@ -65,6 +56,45 @@ end:
        return conn;
 }
 
+int connection_reset_protocol_state(struct relay_connection *connection)
+{
+       int ret = 0;
+
+       switch (connection->type) {
+       case RELAY_DATA:
+               connection->protocol.data.state_id =
+                               DATA_CONNECTION_STATE_RECEIVE_HEADER;
+               memset(&connection->protocol.data.state.receive_header,
+                               0,
+                               sizeof(connection->protocol.data.state.receive_header));
+               connection->protocol.data.state.receive_header.left_to_receive =
+                               sizeof(struct lttcomm_relayd_data_hdr);
+               break;
+       case RELAY_CONTROL:
+               connection->protocol.ctrl.state_id =
+                               CTRL_CONNECTION_STATE_RECEIVE_HEADER;
+               memset(&connection->protocol.ctrl.state.receive_header,
+                               0,
+                               sizeof(connection->protocol.ctrl.state.receive_header));
+               connection->protocol.data.state.receive_header.left_to_receive =
+                               sizeof(struct lttcomm_relayd_hdr);
+               ret = lttng_dynamic_buffer_set_size(
+                               &connection->protocol.ctrl.reception_buffer,
+                               sizeof(struct lttcomm_relayd_hdr));
+               if (ret) {
+                       ERR("Failed to reinitialize control connection reception buffer size to %zu bytes.", sizeof(struct lttcomm_relayd_hdr));
+                       goto end;
+               }
+               break;
+       default:
+               goto end;
+       }
+       DBG("Reset communication state of relay connection (fd = %i)",
+                       connection->sock->fd);
+end:
+       return ret;
+}
+
 struct relay_connection *connection_create(struct lttcomm_sock *sock,
                enum connection_type type)
 {
@@ -75,11 +105,14 @@ struct relay_connection *connection_create(struct lttcomm_sock *sock,
                PERROR("zmalloc relay connection");
                goto end;
        }
-       pthread_mutex_init(&conn->reflock, NULL);
        urcu_ref_init(&conn->ref);
        conn->type = type;
        conn->sock = sock;
        lttng_ht_node_init_ulong(&conn->sock_n, (unsigned long) conn->sock->fd);
+       if (conn->type == RELAY_CONTROL) {
+               lttng_dynamic_buffer_init(&conn->protocol.ctrl.reception_buffer);
+       }
+       connection_reset_protocol_state(conn);
 end:
        return conn;
 }
@@ -94,6 +127,10 @@ static void rcu_free_connection(struct rcu_head *head)
                viewer_session_destroy(conn->viewer_session);
                conn->viewer_session = NULL;
        }
+       if (conn->type == RELAY_CONTROL) {
+               lttng_dynamic_buffer_reset(
+                               &conn->protocol.ctrl.reception_buffer);
+       }
        free(conn);
 }
 
@@ -131,9 +168,7 @@ static void connection_release(struct urcu_ref *ref)
 void connection_put(struct relay_connection *conn)
 {
        rcu_read_lock();
-       pthread_mutex_lock(&conn->reflock);
        urcu_ref_put(&conn->ref, connection_release);
-       pthread_mutex_unlock(&conn->reflock);
        rcu_read_unlock();
 }
 
@@ -145,3 +180,27 @@ void connection_ht_add(struct lttng_ht *relay_connections_ht,
        conn->in_socket_ht = 1;
        conn->socket_ht = relay_connections_ht;
 }
+
+int connection_set_session(struct relay_connection *conn,
+               struct relay_session *session)
+{
+       int ret = 0;
+
+       assert(conn);
+       assert(session);
+       assert(!conn->session);
+
+       if (connection_get(conn)) {
+               if (session_get(session)) {
+                       conn->session = session;
+               } else {
+                       ERR("Failed to get session reference in connection_set_session()");
+                       ret = -1;
+               }
+               connection_put(conn);
+       } else {
+               ERR("Failed to get connection reference in connection_set_session()");
+               ret = -1;
+       }
+       return ret;
+}