[PATCH] ASoC: ops: dynamically allocate struct snd_ctl_elem_value

[PATCH] ASoC: ops: dynamically allocate struct snd_ctl_elem_value

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

This structure is really too larget to be allocated on the stack:

sound/soc/soc-ops.c:435:5: error: stack frame size (1296) exceeds limit (1280) in 'snd_soc_limit_volume' [-Werror,-Wframe-larger-than]

Change the function to dynamically allocate it instead.

There is probably a better way to do it since only two integer fields
inside of that structure are actually used, but this is the simplest
rework for the moment.

Fixes: 783db6851c18 ("ASoC: ops: Enforce platform maximum on initial value")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 sound/soc/soc-ops.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c
index a1a011e6b17c..00c6f1ce7474 100644
--- a/sound/soc/soc-ops.c
+++ b/sound/soc/soc-ops.c
@@ -399,28 +399,32 @@ EXPORT_SYMBOL_GPL(snd_soc_put_volsw_sx);
 static int snd_soc_clip_to_platform_max(struct snd_kcontrol *kctl)
 {
 	struct soc_mixer_control *mc = (struct soc_mixer_control *)kctl->private_value;
-	struct snd_ctl_elem_value uctl;
+	struct snd_ctl_elem_value *uctl;
 	int ret;
 
 	if (!mc->platform_max)
 		return 0;
 
-	ret = kctl->get(kctl, &uctl);
+	uctl = kzalloc(sizeof(*uctl), GFP_KERNEL);
+	if (!uctl)
+		return -ENOMEM;
+
+	ret = kctl->get(kctl, uctl);
 	if (ret < 0)
-		return ret;
+		goto out;
 
-	if (uctl.value.integer.value[0] > mc->platform_max)
-		uctl.value.integer.value[0] = mc->platform_max;
+	if (uctl->value.integer.value[0] > mc->platform_max)
+		uctl->value.integer.value[0] = mc->platform_max;
 
 	if (snd_soc_volsw_is_stereo(mc) &&
-	    uctl.value.integer.value[1] > mc->platform_max)
-		uctl.value.integer.value[1] = mc->platform_max;
+	    uctl->value.integer.value[1] > mc->platform_max)
+		uctl->value.integer.value[1] = mc->platform_max;
 
-	ret = kctl->put(kctl, &uctl);
-	if (ret < 0)
-		return ret;
+	ret = kctl->put(kctl, uctl);
 
-	return 0;
+out:
+	kfree(uctl);
+	return ret;
 }
 
 /**
-- 
2.39.5

Re: [PATCH] ASoC: ops: dynamically allocate struct snd_ctl_elem_value

[Mark Brown]

On Tue, 10 Jun 2025 11:30:53 +0200, Arnd Bergmann wrote:
> This structure is really too larget to be allocated on the stack:
> 
> sound/soc/soc-ops.c:435:5: error: stack frame size (1296) exceeds limit (1280) in 'snd_soc_limit_volume' [-Werror,-Wframe-larger-than]
> 
> Change the function to dynamically allocate it instead.
> 
> There is probably a better way to do it since only two integer fields
> inside of that structure are actually used, but this is the simplest
> rework for the moment.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/1] ASoC: ops: dynamically allocate struct snd_ctl_elem_value
      commit: 7e10d7242ea8a5947878880b912ffa5806520705

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark