[PATCH v2] ASoC: codecs: lpass-wsa-macro: handle unexpected input

[PATCH v2] ASoC: codecs: lpass-wsa-macro: handle unexpected input

[trix]

From: Tom Rix <trix@redhat.com>

Static analysis reports this problem

lpass-wsa-macro.c:1732:6: warning: Array subscript is undefined
        if (wsa->ec_hq[ec_tx]) {
            ^~~~~~~~~~~~~~~~~

The happens because 'ec_tx' is never initialized and there is
no default in switch statement that sets ec_tx.  Add a default
case that returns an error before the array is accessed.

Signed-off-by: Tom Rix <trix@redhat.com>
---
v2:
  - handle the input error, keep switch
---
 sound/soc/codecs/lpass-wsa-macro.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/soc/codecs/lpass-wsa-macro.c b/sound/soc/codecs/lpass-wsa-macro.c
index 1a7fa5492f28..d3ac318fd6b6 100644
--- a/sound/soc/codecs/lpass-wsa-macro.c
+++ b/sound/soc/codecs/lpass-wsa-macro.c
@@ -1727,6 +1727,10 @@ static int wsa_macro_enable_echo(struct snd_soc_dapm_widget *w,
 		val = val & CDC_WSA_RX_MIX_TX1_SEL_MASK;
 		ec_tx = (val >> CDC_WSA_RX_MIX_TX1_SEL_SHFT) - 1;
 		break;
+	default:
+		dev_err(component->dev,	"%s: Invalid shift %u\n",
+			__func__, w->shift);
+		return -EINVAL;
 	}
 
 	if (wsa->ec_hq[ec_tx]) {
-- 
2.26.3

Re: [PATCH v2] ASoC: codecs: lpass-wsa-macro: handle unexpected input

[Srinivas Kandagatla]

Thanks Tom for fixing this.

On 30/04/2021 15:21, trix@redhat.com wrote:
> From: Tom Rix <trix@redhat.com>
> 
> Static analysis reports this problem
> 
> lpass-wsa-macro.c:1732:6: warning: Array subscript is undefined
>          if (wsa->ec_hq[ec_tx]) {
>              ^~~~~~~~~~~~~~~~~
> 
> The happens because 'ec_tx' is never initialized and there is
> no default in switch statement that sets ec_tx.  Add a default
> case that returns an error before the array is accessed.
> 
> Signed-off-by: Tom Rix <trix@redhat.com>
> ---
> v2:
>    - handle the input error, keep switch
> ---
>   sound/soc/codecs/lpass-wsa-macro.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/sound/soc/codecs/lpass-wsa-macro.c b/sound/soc/codecs/lpass-wsa-macro.c
> index 1a7fa5492f28..d3ac318fd6b6 100644
> --- a/sound/soc/codecs/lpass-wsa-macro.c
> +++ b/sound/soc/codecs/lpass-wsa-macro.c
> @@ -1727,6 +1727,10 @@ static int wsa_macro_enable_echo(struct snd_soc_dapm_widget *w,
>   		val = val & CDC_WSA_RX_MIX_TX1_SEL_MASK;
>   		ec_tx = (val >> CDC_WSA_RX_MIX_TX1_SEL_SHFT) - 1;
>   		break;
> +	default:
> +		dev_err(component->dev,	"%s: Invalid shift %u\n",
> +			__func__, w->shift);
> +		return -EINVAL;

With the existing code we should never even touch this default path,

However the changes look safe to me,

Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>


--srini


>   	}
>   
>   	if (wsa->ec_hq[ec_tx]) {
> 

Re: [PATCH v2] ASoC: codecs: lpass-wsa-macro: handle unexpected input

[Mark Brown]

On Fri, 30 Apr 2021 07:21:17 -0700, trix@redhat.com wrote:
> Static analysis reports this problem
> 
> lpass-wsa-macro.c:1732:6: warning: Array subscript is undefined
>         if (wsa->ec_hq[ec_tx]) {
>             ^~~~~~~~~~~~~~~~~
> 
> The happens because 'ec_tx' is never initialized and there is
> no default in switch statement that sets ec_tx.  Add a default
> case that returns an error before the array is accessed.

Applied to

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

Thanks!

[1/1] ASoC: codecs: lpass-wsa-macro: handle unexpected input
      commit: 58f01c7fc81baced84f237554d56847e17b5d730

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