Fix: double unlock of metadata mutex on error

lttng_ustconsumer_sync_metadata must leave the metadata lock
in its initial state. Otherwise an error may result in a
double unlock in the caller.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index 5c7b00317dabb824f378858bb05234347eec424e..7bbfa60a26fc6f90aed740869b0773994cd86ca2 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -2273,10 +2273,10 @@ int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data *ctx,
         * because we locked the metadata thread.
         */
        ret = lttng_ustconsumer_request_metadata(ctx, metadata->chan, 0, 0);
+       pthread_mutex_lock(&metadata->lock);
        if (ret < 0) {
                goto end;
        }
-       pthread_mutex_lock(&metadata->lock);
 
        ret = commit_one_metadata_packet(metadata);
        if (ret <= 0) {