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

[Srinivas Kandagatla]

Thanks Tom for fixing this.

On 30/04/2021 15:21, trix at redhat.com wrote:
> From: Tom Rix <trix at 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 at 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 at linaro.org>


--srini


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