[PATCH 4.14 13/25] ASoC: max98090: Reject invalid values in custom control put()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Mark Brown <broonie@kernel.org>

[ Upstream commit 2fbe467bcbfc760a08f08475eea6bbd4c2874319 ]

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@kernel.org>
Link: https://lore.kernel.org/r/20220420193454.2647908-1-broonie@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@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 3fe09828745a..a25183f6fba6 100644
--- a/sound/soc/codecs/max98090.c
+++ b/sound/soc/codecs/max98090.c
@@ -419,6 +419,9 @@ 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 */
-- 
2.35.1