From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Tue, 20 Dec 2016 20:00:04 +0000 (-0500)
Subject: Fix: double unlock of metadata mutex on error
X-Git-Tag: v2.8.4~3
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=504e362ffb535a616364a82f3de68b92d4c9663d;p=lttng-tools.git

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 c7f208b8d..faf069c0d 100644
--- 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) {