Re: [PATCH v1] sound/pci/hda/patch_realtek: don't call alc_shutup_pins without a spec

Re: [PATCH v1] sound/pci/hda/patch_realtek: don't call alc_shutup_pins without a spec

[Takashi Iwai]

On Mon, 14 Nov 2022 09:20:48 +0100,
Daniil Tatianin wrote:
> 
> alc_shutup_pins always expects the spec to be present, so make sure
> it is before we call it.
> 
> Found by Linux Verification Center (linuxtesting.org) with the SVACE
> static analysis tool.
> 
> Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>

In which path can it be without spec assigned?
That's the internal callback that is set only by the codec driver
where the allocation of codec->spec is mandatory.


thanks,

Takashi


> ---
>  sound/pci/hda/patch_realtek.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
> index 60e3bc124836..2cf4b64971d7 100644
> --- a/sound/pci/hda/patch_realtek.c
> +++ b/sound/pci/hda/patch_realtek.c
> @@ -939,10 +939,12 @@ static inline void alc_shutup(struct hda_codec *codec)
>  {
>  	struct alc_spec *spec = codec->spec;
>  
> +	if (!spec)
> +		return;
>  	if (!snd_hda_get_bool_hint(codec, "shutup"))
>  		return; /* disabled explicitly by hints */
>  
> -	if (spec && spec->shutup)
> +	if (spec->shutup)
>  		spec->shutup(codec);
>  	else
>  		alc_shutup_pins(codec);
> -- 
> 2.25.1
> 

Re: [PATCH v1] sound/pci/hda/patch_realtek: don't call alc_shutup_pins without a spec

[Takashi Iwai]

On Mon, 14 Nov 2022 09:35:10 +0100,
Daniil Tatianin wrote:
> 
> 
> 
> On 11/14/22 11:26 AM, Takashi Iwai wrote:
> > On Mon, 14 Nov 2022 09:20:48 +0100,
> > Daniil Tatianin wrote:
> >> 
> >> alc_shutup_pins always expects the spec to be present, so make sure
> >> it is before we call it.
> >> 
> >> Found by Linux Verification Center (linuxtesting.org) with the SVACE
> >> static analysis tool.
> >> 
> >> Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
> > 
> > In which path can it be without spec assigned?
> > That's the internal callback that is set only by the codec driver
> > where the allocation of codec->spec is mandatory.
> 
> Would you then say that the "if (spec && ...)" that was there before
> was redundant?

Yes.


Takashi