[PATCH] ASoC: cpcap: Check for NULL pointer after calling of_get_child_by_name

[PATCH] ASoC: cpcap: Check for NULL pointer after calling of_get_child_by_name

[Jiasheng Jiang]

If the device does not exist, of_get_child_by_name() will return NULL
pointer.
And devm_snd_soc_register_component() does not check it.
Also, I have noticed that cpcap_codec_driver has not been used yet.
Therefore, it should be better to check it in order to avoid the future
dereference of the NULL pointer.

Fixes: f6cdf2d3445d ("ASoC: cpcap: new codec")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 sound/soc/codecs/cpcap.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sound/soc/codecs/cpcap.c b/sound/soc/codecs/cpcap.c
index 05bbacd0d174..f1c13f42e1c1 100644
--- a/sound/soc/codecs/cpcap.c
+++ b/sound/soc/codecs/cpcap.c
@@ -1667,6 +1667,8 @@ static int cpcap_codec_probe(struct platform_device *pdev)
 {
 	struct device_node *codec_node =
 		of_get_child_by_name(pdev->dev.parent->of_node, "audio-codec");
+	if (!codec_node)
+		return -ENODEV;
 
 	pdev->dev.of_node = codec_node;
 
-- 
2.25.1

Re: [PATCH] ASoC: cpcap: Check for NULL pointer after calling of_get_child_by_name

[Mark Brown]

On Tue, 11 Jan 2022 10:50:48 +0800, Jiasheng Jiang wrote:
> If the device does not exist, of_get_child_by_name() will return NULL
> pointer.
> And devm_snd_soc_register_component() does not check it.
> Also, I have noticed that cpcap_codec_driver has not been used yet.
> Therefore, it should be better to check it in order to avoid the future
> dereference of the NULL pointer.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-linus

Thanks!

[1/1] ASoC: cpcap: Check for NULL pointer after calling of_get_child_by_name
      commit: f7a6021aaf02088870559f82fc13c58cda7fea1a

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark