[PATCH 1/2] ASoC: max98090: Reject invalid values in custom control put()

[Mark Brown]

The max98090 driver has a custom put function for some controls which can
only be updated in certain circumstances which makes no effort to validate
that input is suitable for the control, allowing out of spec values to be
written to the hardware and presented to userspace. Fix this by returning
an error when invalid values are written.

Signed-off-by: Mark Brown <broonie at kernel.org>
---
 sound/soc/codecs/max98090.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/sound/soc/codecs/max98090.c b/sound/soc/codecs/max98090.c
index b45ec35cd63c..6d9261346842 100644
--- a/sound/soc/codecs/max98090.c
+++ b/sound/soc/codecs/max98090.c
@@ -413,6 +413,9 @@ static int max98090_put_enab_tlv(struct snd_kcontrol *kcontrol,
 
 	val = (val >> mc->shift) & mask;
 
+	if (sel < 0 || sel > mc->max)
+		return -EINVAL;
+
 	*select = sel;
 
 	/* Setting a volume is only valid if it is already On */
-- 
2.30.2