[PATCH v3 1/6] ALSA: vmaster: Return error for invalid input values

[Takashi Iwai <tiwai@xxxxxxx>]

So far the vmaster code has been tolerant about the input values and
accepts any values by correcting internally.  But now our own selftest
starts complaining about this behavior, so let's be picky and change
the behavior to return -EINVAL for invalid input values instead.

Reported-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>
Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@xxxxxxxxxxxxx
Reviewed-by: Jaroslav Kysela <perex@xxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
 sound/core/vmaster.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/sound/core/vmaster.c b/sound/core/vmaster.c
index 04a57f7be6ea..c657659b236c 100644
--- a/sound/core/vmaster.c
+++ b/sound/core/vmaster.c
@@ -198,6 +198,12 @@ static int follower_put(struct snd_kcontrol *kcontrol,
 	err = follower_init(follower);
 	if (err < 0)
 		return err;
+	for (ch = 0; ch < follower->info.count; ch++) {
+		if (ucontrol->value.integer.value[ch] < follower->info.min_val ||
+		    ucontrol->value.integer.value[ch] > follower->info.max_val)
+			return -EINVAL;
+	}
+
 	for (ch = 0; ch < follower->info.count; ch++) {
 		if (follower->vals[ch] != ucontrol->value.integer.value[ch]) {
 			changed = 1;
@@ -365,6 +371,8 @@ static int master_put(struct snd_kcontrol *kcontrol,
 	new_val = ucontrol->value.integer.value[0];
 	if (new_val == old_val)
 		return 0;
+	if (new_val < master->info.min_val || new_val > master->info.max_val)
+		return -EINVAL;
 
 	err = sync_followers(master, old_val, new_val);
 	if (err < 0)
-- 
2.43.0