[alsa-devel] [PATCH 1/2] ASoC: codecs: ad193x: Fix memory corruption on BE 64b systems

[gianluca]

On 06/26/2019 12:49 PM, Codrin Ciubotariu wrote:
> Since change_bit() requires unsigned long*, making this cast on an
> unsigned int variable will change a wrong bit on BE platforms, causing
> memory corruption. Replace this function with a simple XOR.
>
> Fixes: 90f6e6803139 ("ASoC: codecs: ad193x: Fix frame polarity for DSP_A format")
> Reported-by: Dan Carpenter <dan.carpenter at oracle.com>
> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu at microchip.com>
> ---
>  sound/soc/codecs/ad193x.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/sound/soc/codecs/ad193x.c b/sound/soc/codecs/ad193x.c
> index 05f4514048e2..3ebc0524f4b2 100644
> --- a/sound/soc/codecs/ad193x.c
> +++ b/sound/soc/codecs/ad193x.c
> @@ -240,10 +240,8 @@ static int ad193x_set_dai_fmt(struct snd_soc_dai *codec_dai,
>  	}
>
>  	/* For DSP_*, LRCLK's polarity must be inverted */
> -	if (fmt & SND_SOC_DAIFMT_DSP_A) {
> -		change_bit(ffs(AD193X_DAC_LEFT_HIGH) - 1,
> -			   (unsigned long *)&dac_fmt);
> -	}
> +	if (fmt & SND_SOC_DAIFMT_DSP_A)
> +		dac_fmt ^= AD193X_DAC_LEFT_HIGH;
>

BigEndian RULEZ! ;-P


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