output_internal: protect attribute "fail_timer" with mutex

2 files changed, 7 insertions, 1 deletions

diff --git a/src/output_internal.h b/src/output_internal.h
index 72596c1c3..b863c9ecc 100644
--- a/src/output_internal.h
+++ b/src/output_internal.h
@@ -131,7 +131,8 @@ struct audio_output {
 	const struct music_pipe *pipe;
 
 	/**
-	 * This mutex protects #open, #chunk and #chunk_finished.
+	 * This mutex protects #open, #fail_timer, #chunk and
+	 * #chunk_finished.
 	 */
 	GMutex *mutex;
 
diff --git a/src/output_thread.c b/src/output_thread.c
index e652eae57..b97694169 100644
--- a/src/output_thread.c
+++ b/src/output_thread.c
@@ -105,7 +105,12 @@ ao_play_chunk(struct audio_output *ao, const struct music_chunk *chunk)
 
 			/* don't automatically reopen this device for
 			   10 seconds */
+			g_mutex_lock(ao->mutex);
+
+			assert(ao->fail_timer == NULL);
 			ao->fail_timer = g_timer_new();
+
+			g_mutex_unlock(ao->mutex);
 			return false;
 		}