[PATCH 06/11] ALSA: scarlett2: Add missing mutex lock around get meter levels

["Geoffrey D. Bennett" <g@xxxxx>]

As scarlett2_meter_ctl_get() uses meter_level_map[], the data_mutex
should be locked while accessing it.

Signed-off-by: Geoffrey D. Bennett <g@xxxxx>
Fixes: 2b17abb0dec4 ("ALSA: scarlett2: Remap Level Meter values")
---
 sound/usb/mixer_scarlett2.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/sound/usb/mixer_scarlett2.c b/sound/usb/mixer_scarlett2.c
index f1636a1614da..73f5badceb19 100644
--- a/sound/usb/mixer_scarlett2.c
+++ b/sound/usb/mixer_scarlett2.c
@@ -3880,10 +3880,12 @@ static int scarlett2_meter_ctl_get(struct snd_kcontrol *kctl,
 	u16 meter_levels[SCARLETT2_MAX_METERS];
 	int i, err;
 
+	mutex_lock(&private->data_mutex);
+
 	err = scarlett2_usb_get_meter_levels(elem->head.mixer, elem->channels,
 					     meter_levels);
 	if (err < 0)
-		return err;
+		goto unlock;
 
 	/* copy & translate from meter_levels[] using meter_level_map[] */
 	for (i = 0; i < elem->channels; i++) {
@@ -3898,7 +3900,10 @@ static int scarlett2_meter_ctl_get(struct snd_kcontrol *kctl,
 		ucontrol->value.integer.value[i] = value;
 	}
 
-	return 0;
+unlock:
+	mutex_unlock(&private->data_mutex);
+
+	return err;
 }
 
 static const struct snd_kcontrol_new scarlett2_meter_ctl = {
-- 
2.43.0