Re: [PATCH] ASoC: soc-pcm: don't ignore -EINVAL on soc_pcm_ret()

[Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>]

Hi Hans

Thank you for the feedback

> -EINVAL really should only be used upon invalid parameters coming from
> userspace and in that case we don't want to log an error since we do
> not want to give userspace a way to do a denial-of-service attack
> on the syslog / diskspace.
>
> I'm not convinced that this change is a good idea, but I also
> have no strong objections.

Thanks but hmm...
In reality, -EINVAL is used not only from userspace, and many inside
kernel functions are using it. So don't indicate -EINVAL for all case
is over-kill in real world. But thank you for clarify the situation.
I think indicating it on comment is good idea.


> > @@ -2560,8 +2559,8 @@ static int dpcm_fe_dai_prepare(struct snd_pcm_substream *substream)
> >  			     fe->dai_link->name);
> >  		dev_dbg(fe->dev, "ASoC: no backend DAIs enabled for %s\n",
> >  			fe->dai_link->name);
> > -		ret = -EINVAL;
> > -		goto out;
> > +		/* don't use soc_pcm_ret() to lower error log severity */
> > +		return -EINVAL;
> 
> You cannot just do a return here, you are now missing these 2 lines from
> the "goto out" path:

Oh, yes, indeed.
Thank you for pointing it. Will fix in v2

Thank you for your help !!

Best regards
---
Kuninori Morimoto