Fix: Consumer sockets leak on error

[lttng-tools.git] / src / common / consumer.c

diff --git a/src/common/consumer.c b/src/common/consumer.c
index 0e73bc9b8aeda6766953fbd381fcc05c370f795c..5dc1d92b40685598e1c841b8d3128073aeed65ba 100644 (file)
--- a/src/common/consumer.c
+++ b/src/common/consumer.c
@@ -127,6 +127,12 @@ void consumer_steal_stream_key(int key, struct lttng_ht *ht)
        rcu_read_unlock();
 }
 
+/*
+ * Return a channel object for the given key.
+ *
+ * RCU read side lock MUST be acquired before calling this function and
+ * protects the channel ptr.
+ */
 static struct lttng_consumer_channel *consumer_find_channel(int key)
 {
        struct lttng_ht_iter iter;
@@ -138,8 +144,6 @@ static struct lttng_consumer_channel *consumer_find_channel(int key)
                return NULL;
        }
 
-       rcu_read_lock();
-
        lttng_ht_lookup(consumer_data.channel_ht, (void *)((unsigned long) key),
                        &iter);
        node = lttng_ht_iter_get_node_ulong(&iter);
@@ -147,8 +151,6 @@ static struct lttng_consumer_channel *consumer_find_channel(int key)
                channel = caa_container_of(node, struct lttng_consumer_channel, node);
        }
 
-       rcu_read_unlock();
-
        return channel;
 }
 
@@ -475,6 +477,8 @@ struct lttng_consumer_stream *consumer_allocate_stream(
                goto end;
        }
 
+       rcu_read_lock();
+
        /*
         * Get stream's channel reference. Needed when adding the stream to the
         * global hash table.
@@ -531,9 +535,12 @@ struct lttng_consumer_stream *consumer_allocate_stream(
                        stream->path_name, stream->key, stream->shm_fd, stream->wait_fd,
                        (unsigned long long) stream->mmap_len, stream->out_fd,
                        stream->net_seq_idx, stream->session_id);
+
+       rcu_read_unlock();
        return stream;
 
 error:
+       rcu_read_unlock();
        free(stream);
 end:
        return NULL;
@@ -910,7 +917,7 @@ static int consumer_update_poll_array(
                 * changed where this function will be called back again.
                 */
                if (stream->state != LTTNG_CONSUMER_ACTIVE_STREAM ||
-                               stream->endpoint_status) {
+                               stream->endpoint_status == CONSUMER_ENDPOINT_INACTIVE) {
                        continue;
                }
                DBG("Active FD %d", stream->wait_fd);
@@ -1260,6 +1267,8 @@ end:
  * core function for writing trace buffers to either the local filesystem or
  * the network.
  *
+ * It must be called with the stream lock held.
+ *
  * Careful review MUST be put if any changes occur!
  *
  * Returns the number of bytes written
@@ -1412,6 +1421,8 @@ end:
 /*
  * Splice the data from the ring buffer to the tracefile.
  *
+ * It must be called with the stream lock held.
+ *
  * Returns the number of bytes spliced.
  */
 ssize_t lttng_consumer_on_read_subbuffer_splice(
@@ -1943,7 +1954,7 @@ static void validate_endpoint_status_data_stream(void)
        rcu_read_lock();
        cds_lfht_for_each_entry(data_ht->ht, &iter.iter, stream, node.node) {
                /* Validate delete flag of the stream */
-               if (stream->endpoint_status != CONSUMER_ENDPOINT_INACTIVE) {
+               if (stream->endpoint_status == CONSUMER_ENDPOINT_ACTIVE) {
                        continue;
                }
                /* Delete it right now */
@@ -1968,7 +1979,7 @@ static void validate_endpoint_status_metadata_stream(
        rcu_read_lock();
        cds_lfht_for_each_entry(metadata_ht->ht, &iter.iter, stream, node.node) {
                /* Validate delete flag of the stream */
-               if (!stream->endpoint_status) {
+               if (stream->endpoint_status == CONSUMER_ENDPOINT_ACTIVE) {
                        continue;
                }
                /*
@@ -2443,7 +2454,7 @@ end:
  */
 void *consumer_thread_sessiond_poll(void *data)
 {
-       int sock, client_socket, ret;
+       int sock = -1, client_socket, ret;
        /*
         * structure to poll for incoming data on communication socket avoids
         * making blocking sockets.
@@ -2503,6 +2514,13 @@ void *consumer_thread_sessiond_poll(void *data)
                goto end;
        }
 
+       /* This socket is not useful anymore. */
+       ret = close(client_socket);
+       if (ret < 0) {
+               PERROR("close client_socket");
+       }
+       client_socket = -1;
+
        /* update the polling structure to poll on the established socket */
        consumer_sockpoll[1].fd = sock;
        consumer_sockpoll[1].events = POLLIN | POLLPRI;
@@ -2546,6 +2564,20 @@ end:
         */
        notify_thread_pipe(ctx->consumer_data_pipe[1]);
 
+       /* Cleaning up possibly open sockets. */
+       if (sock >= 0) {
+               ret = close(sock);
+               if (ret < 0) {
+                       PERROR("close sock sessiond poll");
+               }
+       }
+       if (client_socket >= 0) {
+               ret = close(sock);
+               if (ret < 0) {
+                       PERROR("close client_socket sessiond poll");
+               }
+       }
+
        rcu_unregister_thread();
        return NULL;
 }