Re: [PATCH 1/2] ASoC: soc-core: copy the DAI link names into the card

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found no new issues
in this patch, but noticed 1 related pre-existing issue it does not
introduce:
- [Medium] ASoC: soc-core: memory leak in snd_soc_of_get_dlc() [1]
--

commit fe7efa2dfe30cec1a0e194d20cca010f7a414abc
Author: Tyler Baker <tyler.baker@oss.qualcomm.com>

ASoC: soc-core: copy the DAI link names into the card

This commit duplicates the component DAI name onto the card device in
snd_soc_of_get_dai_link_codecs() and snd_soc_of_get_dai_link_cpus() so the
name remains valid across component unbind and rebind.

> diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
> index f33bece378b61..0e62965e35aaa 100644
> --- a/sound/soc/soc-core.c
> +++ b/sound/soc/soc-core.c

[ ... ]

> @@ -3282,6 +3294,8 @@ int snd_soc_of_get_dai_link_codecs(struct device *dev,
>  	/* Parse the list */
>  	for_each_link_codecs(dai_link, index, component) {
>  		ret = snd_soc_of_get_dlc(of_node, NULL, component, index);
> +		if (!ret)
> +			ret = snd_soc_of_dup_dai_name(dev, component);
>  		if (ret)
>  			goto err;
>  	}

[Severity: Medium]
This problem wasn't introduced by this patch, but does snd_soc_of_get_dlc()
[1] leak the device_node reference in args->np when snd_soc_get_dlc()
fails?

sound/soc/soc-core.c:snd_soc_of_get_dlc() {
	if (!args)
		args = &__args;

	ret = of_parse_phandle_with_args(of_node, "sound-dai",
					 "#sound-dai-cells", index, args);
	if (ret)
		return ret;

	return snd_soc_get_dlc(args, dlc);
}

of_parse_phandle_with_args() acquires a reference on args->np, which
snd_soc_get_dlc() only transfers to dlc->of_node on success.  When
snd_soc_get_dlc() fails (for example with -EPROBE_DEFER) and the caller
passed a NULL args pointer as done here and in
snd_soc_of_get_dai_link_cpus(), __args goes out of scope without
of_node_put() being called.

[1] https://sashiko.dev/#/bug/linux-11ae6ad5-0cce-4928-9290-e7723e9f7638

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261106054333.2748248-1-tyler.baker@oss.qualcomm.com?part=1