Re: [PATCH] staging: greybus: audio: Add missing unlock in gbaudio_dapm_free_controls()

[Vaibhav Agarwal]

On Fri, Dec 4, 2020 at 2:10 PM Johan Hovold <johan@xxxxxxxxxx> wrote:
>
> On Fri, Dec 04, 2020 at 10:13:50AM +0800, Wang Hai wrote:
> > Add the missing unlock before return from function
> > gbaudio_dapm_free_controls() in the error handling case.
> >
> > Fixes: 510e340efe0c ("staging: greybus: audio: Add helper APIs for dynamic audio module")
> > Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> > Signed-off-by: Wang Hai <wanghai38@xxxxxxxxxx>
> > ---
> >  drivers/staging/greybus/audio_helper.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/staging/greybus/audio_helper.c b/drivers/staging/greybus/audio_helper.c
> > index 237531ba60f3..293675dbea10 100644
> > --- a/drivers/staging/greybus/audio_helper.c
> > +++ b/drivers/staging/greybus/audio_helper.c
> > @@ -135,6 +135,7 @@ int gbaudio_dapm_free_controls(struct snd_soc_dapm_context *dapm,
> >               if (!w) {
> >                       dev_err(dapm->dev, "%s: widget not found\n",
> >                               widget->name);
> > +                     mutex_unlock(&dapm->card->dapm_mutex);
> >                       return -EINVAL;
> >               }
> >               widget++;
>
> This superficially looks correct, but there seems to be another bug in
> this function. It can be used free an array of widgets, but if one of
> them isn't found we just leak the rest. Perhaps that return should
> rather be "widget++; continue;".
>
> Vaibhav?

Thanks Wang for sharing the patch. As already pointed by Johan, this
function indeed has another bug as well.
Pls feel free to share the patch as suggested above.

--
vaibhav

>
> Johan