[PATCH 7.1.y] ASoC: tas2562: Validate values for volume writes

From: Mark Brown <[email protected]>

[ Upstream commit 8fb41964f7e4e4207c8999af2056894caa7a252a ]

tas2562_volume_control_put() does not do any validation of the control
value written by userspace, it uses it to look up a value in a fixed
size array which can easily be overflowed and then writes whatever value
it gets back to the device.  Add validation that we are loading a value
we have in the array.

Cc: [email protected]
Reviewed-by: Cezary Rojewski <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
 sound/soc/codecs/tas2562.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/tas2562.c b/sound/soc/codecs/tas2562.c
index 1c36c910f47a6..74c4275ef29ce 100644
--- a/sound/soc/codecs/tas2562.c
+++ b/sound/soc/codecs/tas2562.c
@@ -472,10 +472,15 @@ static int tas2562_volume_control_put(struct snd_kcontrol *kcontrol,
 {
 	struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
 	struct tas2562_data *tas2562 = snd_soc_component_get_drvdata(component);
-	int ret;
+	int ret, index;
 	u32 reg_val;
 
-	reg_val = float_vol_db_lookup[ucontrol->value.integer.value[0]/2];
+	index = ucontrol->value.integer.value[0] / 2;
+	if (index < 0 || index >= ARRAY_SIZE(float_vol_db_lookup))
+		return -EINVAL;
+
+	reg_val = float_vol_db_lookup[index];
+
 	/*
 	 * The device applies the 32-bit coefficient to the playback path on
 	 * the write to DVC_CFG4 (the LSB, book 0 page 2 reg 0x0F), so the
-- 
2.53.0