ASoC: max98090: Reject invalid values in custom control put()

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>

diff --git a/sound/soc/codecs/max98090.c b/sound/soc/codecs/max98090.c
index b45ec35..6d92613 100644 (file)
--- 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 */