[PATCH 1/2] ASoC: SOF: Prevent NULL dereference in sof_pcm_dai_link_fixup()

[Pierre-Louis Bossart]

On 3/18/22 02:12, Dan Carpenter wrote:
> The "dia" pointer can be NULL, so handle that condition first before
> storing "dia->private".
> 
> Fixes: 839e484f9e17 ("ASoC: SOF: make struct snd_sof_dai IPC agnostic")
> Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>

Thanks for the patch.

This part will be removed in follow-up patches, likely the reason why 
this problem was missed.

Acked-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>

> ---
>   sound/soc/sof/pcm.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/sound/soc/sof/pcm.c b/sound/soc/sof/pcm.c
> index 1661b0bc6f12..71f5bce0c4c7 100644
> --- a/sound/soc/sof/pcm.c
> +++ b/sound/soc/sof/pcm.c
> @@ -702,7 +702,7 @@ int sof_pcm_dai_link_fixup(struct snd_soc_pcm_runtime *rtd, struct snd_pcm_hw_pa
>   	struct snd_sof_dai *dai =
>   		snd_sof_find_dai(component, (char *)rtd->dai_link->name);
>   	struct snd_sof_dev *sdev = snd_soc_component_get_drvdata(component);
> -	struct sof_dai_private_data *private = dai->private;
> +	struct sof_dai_private_data *private;
>   	struct snd_soc_dpcm *dpcm;
>   
>   	/* no topology exists for this BE, try a common configuration */
> @@ -727,6 +727,7 @@ int sof_pcm_dai_link_fixup(struct snd_soc_pcm_runtime *rtd, struct snd_pcm_hw_pa
>   	/* read format from topology */
>   	snd_mask_none(fmt);
>   
> +	private = dai->private;
>   	switch (private->comp_dai->config.frame_fmt) {
>   	case SOF_IPC_FRAME_S16_LE:
>   		snd_mask_set_format(fmt, SNDRV_PCM_FORMAT_S16_LE);