[alsa-devel] [PATCH] sound: hdmi: avoid dereferencing uninitialized 'jack' pointer

[Arnd Bergmann]

On Tuesday 16 February 2016 18:10:02 Takashi Iwai wrote:
> diff --git a/include/sound/jack.h b/include/sound/jack.h
> index 23bede121c78..a27c253a3207 100644
> --- a/include/sound/jack.h
> +++ b/include/sound/jack.h
> @@ -99,6 +99,7 @@ void snd_jack_report(struct snd_jack *jack, int status);
>  static inline int snd_jack_new(struct snd_card *card, const char *id, int type,
>                                struct snd_jack **jack, bool initial_kctl, bool phantom_jack)
>  {
> +       *jack = NULL;
>         return 0;
>  }
>  
> diff --git a/sound/pci/hda/hda_jack.c b/sound/pci/hda/hda_jack.c
> index a33234e04d4f..babd3a8864a1 100644
> --- a/sound/pci/hda/hda_jack.c
> +++ b/sound/pci/hda/hda_jack.c
> @@ -403,10 +403,12 @@ int snd_hda_jack_add_kctl(struct hda_codec *codec, hda_nid_t nid,
>  
>         jack->phantom_jack = !!phantom_jack;
>         jack->type = type;
> -       jack->jack->private_data = jack;
> -       jack->jack->private_free = hda_free_jack_priv;
> -       state = snd_hda_jack_detect(codec, nid);
> -       snd_jack_report(jack->jack, state ? jack->type : 0);
> +       if (jack->jack) {
> +               jack->jack->private_data = jack;
> +               jack->jack->private_free = hda_free_jack_priv;
> +               state = snd_hda_jack_detect(codec, nid);
> +               snd_jack_report(jack->jack, state ? jack->type : 0);
> +       }
>  
>         return 0;
>  }
> diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
> index 8ee78dbd4c60..34a7b3aaba11 100644
> --- a/sound/pci/hda/patch_hdmi.c
> +++ b/sound/pci/hda/patch_hdmi.c
> @@ -2158,8 +2158,10 @@ static int add_acomp_jack_kctl(struct hda_codec *codec,
>         if (err < 0)
>                 return err;
>         per_pin->acomp_jack = jack;
> -       jack->private_data = per_pin;
> -       jack->private_free = free_acomp_jack_priv;
> +       if (jack) {
> +               jack->private_data = per_pin;
> +               jack->private_free = free_acomp_jack_priv;
> +       }
>         return 0;
>  }
> 
Looks good to me.

Acked-by: Arnd Bergmann <arnd at arndb.de>