[PATCH AUTOSEL 4.19 2/6] ASoC: max98090: Reject invalid values in custom control put()

From: Sasha Levin
Date: Tue May 10 2022 - 11:58:01 EST


From: Mark Brown <broonie@xxxxxxxxxx>

[ 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@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220420193454.2647908-1-broonie@xxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 a5b0c40ee545..6e5a4e757bf1 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