[alsa-devel] [ALSA hda_codec 1/1] NULL pointer deference fixes for slave_dig_outs

[Takashi Iwai]

At Sat, 13 Sep 2008 04:18:46 -0700,
robbat2 at gentoo.org wrote:
> 
> From: Robin H. Johnson <robbat2 at gentoo.org>
> 
> The new multiple digital output code forgot to check the slave_dig_outs for
> NULL in several places. This manifests as an OOPS when changing volume amongst
> other things.
> 
> Signed-off-by: Robin H. Johnson <robbat2 at gentoo.org>

I already applied a patch from Herton that fixes the very same issue.

Thanks anyway!


Takashi

> 
> diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
> index 696d77e..b22061b 100644
> --- a/sound/pci/hda/hda_codec.c
> +++ b/sound/pci/hda/hda_codec.c
> @@ -1462,14 +1462,15 @@ static int snd_hda_spdif_default_put(struct snd_kcontrol *kcontrol,
>  					  AC_VERB_SET_DIGI_CONVERT_2,
>  					  val >> 8);
>  
> -		for (d = codec->slave_dig_outs; *d; d++) {
> -			snd_hda_codec_write_cache(codec, *d, 0,
> -					  AC_VERB_SET_DIGI_CONVERT_1,
> -					  val & 0xff);
> -			snd_hda_codec_write_cache(codec, *d, 0,
> -					  AC_VERB_SET_DIGI_CONVERT_2,
> -					  val >> 8);
> -		}
> +		if (codec->slave_dig_outs)
> +			for (d = codec->slave_dig_outs; *d; d++) {
> +				snd_hda_codec_write_cache(codec, *d, 0,
> +						  AC_VERB_SET_DIGI_CONVERT_1,
> +						  val & 0xff);
> +				snd_hda_codec_write_cache(codec, *d, 0,
> +						  AC_VERB_SET_DIGI_CONVERT_2,
> +						  val >> 8);
> +			}
>  	}
>  
>  	mutex_unlock(&codec->spdif_mutex);
> @@ -1507,10 +1508,12 @@ static int snd_hda_spdif_out_switch_put(struct snd_kcontrol *kcontrol,
>  					  AC_VERB_SET_DIGI_CONVERT_1,
>  					  val & 0xff);
>  
> -		for (d = codec->slave_dig_outs; *d; d++)
> -			snd_hda_codec_write_cache(codec, *d, 0,
> -					  AC_VERB_SET_DIGI_CONVERT_1,
> -					  val & 0xff);
> +		if (codec->slave_dig_outs)
> +			for (d = codec->slave_dig_outs; *d; d++)
> +				snd_hda_codec_write_cache(codec, *d, 0,
> +						  AC_VERB_SET_DIGI_CONVERT_1,
> +						  val & 0xff);
> +
>  		/* unmute amp switch (if any) */
>  		if ((get_wcaps(codec, nid) & AC_WCAP_OUT_AMP) &&
>  		    (val & AC_DIG1_ENABLE))
> @@ -1664,9 +1667,10 @@ static int snd_hda_spdif_in_switch_put(struct snd_kcontrol *kcontrol,
>  		snd_hda_codec_write_cache(codec, nid, 0,
>  					  AC_VERB_SET_DIGI_CONVERT_1, val);
>  
> -		for (d = codec->slave_dig_outs; *d; d++)
> -			snd_hda_codec_write_cache(codec, *d, 0,
> -					  AC_VERB_SET_DIGI_CONVERT_1, val);
> +		if (codec->slave_dig_outs)
> +			for (d = codec->slave_dig_outs; *d; d++)
> +				snd_hda_codec_write_cache(codec, *d, 0,
> +						  AC_VERB_SET_DIGI_CONVERT_1, val);
>  	}
>  	mutex_unlock(&codec->spdif_mutex);
>  	return change;
> @@ -2617,10 +2621,11 @@ static void setup_dig_out_stream(struct hda_codec *codec, hda_nid_t nid,
>  		snd_hda_codec_write(codec, nid, 0, AC_VERB_SET_DIGI_CONVERT_1,
>  			    codec->spdif_ctls & ~AC_DIG1_ENABLE & 0xff);
>  
> -		for (d = codec->slave_dig_outs; *d; d++)
> -			snd_hda_codec_write(codec, *d, 0,
> -					AC_VERB_SET_DIGI_CONVERT_1,
> -				    codec->spdif_ctls & ~AC_DIG1_ENABLE & 0xff);
> +		if (codec->slave_dig_outs)
> +			for (d = codec->slave_dig_outs; *d; d++)
> +				snd_hda_codec_write(codec, *d, 0,
> +						AC_VERB_SET_DIGI_CONVERT_1,
> +					    codec->spdif_ctls & ~AC_DIG1_ENABLE & 0xff);
>  	}
>  	snd_hda_codec_setup_stream(codec, nid, stream_tag, 0, format);
>  	/* turn on again (if needed) */
> @@ -2628,10 +2633,11 @@ static void setup_dig_out_stream(struct hda_codec *codec, hda_nid_t nid,
>  		snd_hda_codec_write(codec, nid, 0, AC_VERB_SET_DIGI_CONVERT_1,
>  				    codec->spdif_ctls & 0xff);
>  
> -		for (d = codec->slave_dig_outs; *d; d++)
> -			snd_hda_codec_write(codec, *d, 0,
> -					AC_VERB_SET_DIGI_CONVERT_1,
> -				    codec->spdif_ctls & 0xff);
> +		if (codec->slave_dig_outs)
> +			for (d = codec->slave_dig_outs; *d; d++)
> +				snd_hda_codec_write(codec, *d, 0,
> +						AC_VERB_SET_DIGI_CONVERT_1,
> +					    codec->spdif_ctls & 0xff);
>  	}
>  
>  }
> -- 
> 1.6.0.1
>