[pulseaudio-discuss] [PATCH v2] sink-input, source-output: fix unitialized variable access

[Tanu Kaskinen]

The volume_map variable was initialized only for PCM streams, but the
variable was passed to pa_cvolume_remap() also for non-PCM streams. The
volume remapping is never necessary for passthrough streams (PCM or
not), because no volume will be applied anyway, so let's skip the
pa_cvolume_remap() call for all passthrough streams.
---

Changes in v2:
 - Don't remap PCM passthrough streams.

 src/pulsecore/sink-input.c    | 8 ++++++--
 src/pulsecore/source-output.c | 8 ++++++--
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/pulsecore/sink-input.c b/src/pulsecore/sink-input.c
index 5a55e93a5..bc42a9b19 100644
--- a/src/pulsecore/sink-input.c
+++ b/src/pulsecore/sink-input.c
@@ -364,7 +364,7 @@ int pa_sink_input_new(
 
     /* Routing is done. We have a sink and a format. */
 
-    if (data->volume_is_set && pa_format_info_is_pcm(data->format)) {
+    if (data->volume_is_set && !pa_sink_input_new_data_is_passthrough(data)) {
         /* If volume is set, we need to save the original data->channel_map,
          * so that we can remap the volume from the original channel map to the
          * final channel map of the stream in case data->channel_map gets
@@ -372,6 +372,10 @@ int pa_sink_input_new(
         r = pa_stream_get_volume_channel_map(&data->volume, data->channel_map_is_set ? &data->channel_map : NULL, data->format, &volume_map);
         if (r < 0)
             return r;
+    } else {
+        /* Initialize volume_map to invalid state. We check the state later to
+         * determine if volume remapping is needed. */
+        pa_channel_map_init(&volume_map);
     }
 
     /* Now populate the sample spec and channel map according to the final
@@ -403,7 +407,7 @@ int pa_sink_input_new(
     if (!data->volume_writable)
         data->save_volume = false;
 
-    if (data->volume_is_set)
+    if (pa_channel_map_valid(&volume_map))
         /* The original volume channel map may be different than the final
          * stream channel map, so remapping may be needed. */
         pa_cvolume_remap(&data->volume, &volume_map, &data->channel_map);
diff --git a/src/pulsecore/source-output.c b/src/pulsecore/source-output.c
index bcef51fdb..e4ed43804 100644
--- a/src/pulsecore/source-output.c
+++ b/src/pulsecore/source-output.c
@@ -306,7 +306,7 @@ int pa_source_output_new(
 
     /* Routing is done. We have a source and a format. */
 
-    if (data->volume_is_set && pa_format_info_is_pcm(data->format)) {
+    if (data->volume_is_set && !pa_source_output_new_data_is_passthrough(data)) {
         /* If volume is set, we need to save the original data->channel_map,
          * so that we can remap the volume from the original channel map to the
          * final channel map of the stream in case data->channel_map gets
@@ -314,6 +314,10 @@ int pa_source_output_new(
         r = pa_stream_get_volume_channel_map(&data->volume, data->channel_map_is_set ? &data->channel_map : NULL, data->format, &volume_map);
         if (r < 0)
             return r;
+    } else {
+        /* Initialize volume_map to invalid state. We check the state later to
+         * determine if volume remapping is needed. */
+        pa_channel_map_init(&volume_map);
     }
 
     /* Now populate the sample spec and channel map according to the final
@@ -341,7 +345,7 @@ int pa_source_output_new(
     if (!data->volume_writable)
         data->save_volume = false;
 
-    if (data->volume_is_set)
+    if (pa_channel_map_valid(&volume_map))
         /* The original volume channel map may be different than the final
          * stream channel map, so remapping may be needed. */
         pa_cvolume_remap(&data->volume, &volume_map, &data->channel_map);
-- 
2.17.0