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

[Daniil Tatianin]

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 at 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? Should we remove it perhaps to avoid further confusion about 
it being optional? The else branch with alc_shutup_pins would crash if 
it was null anyway.

Thanks

> 
> 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
>>