Re: [PATCH 1/2] ASoC: samsung: odroid: fix an use-after-free issue for codec

[Krzysztof Kozlowski]

On Sat, 13 Jul 2019 at 05:48, Wen Yang  wrote:
>
> The codec variable is still being used after the of_node_put() call,
> which may result in use-after-free.
>
> Fixes: bc3cf17b575a ("ASoC: samsung: odroid: Add support for secondary CPU 
> DAI")
> Signed-off-by: Wen Yang 
> Cc: Krzysztof Kozlowski 
> Cc: Sangbeom Kim 
> Cc: Sylwester Nawrocki 
> Cc: Liam Girdwood 
> Cc: Mark Brown 
> Cc: Jaroslav Kysela 
> Cc: Takashi Iwai 
> Cc: alsa-de...@alsa-project.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  sound/soc/samsung/odroid.c | 6 --
>  1 file changed, 4 insertions(+), 2 deletions(-)

Reviewed-by: Krzysztof Kozlowski 

Best regards,
Krzysztof

Re: [PATCH 1/2] ASoC: samsung: odroid: fix an use-after-free issue for codec

[Markus Elfring]

> @@ -317,6 +316,7 @@ static int odroid_audio_probe(struct platform_device 
> *pdev)

>   goto err_put_clk_i2s;

>   }

>

> + of_node_put(codec);


I would prefer to avoid a bit of duplicate source code also at this place.
Thus I would find a statement like “goto put_node;” more appropriate here.


>   return 0;

>

>  err_put_clk_i2s:



Regards,
Markus

[PATCH 1/2] ASoC: samsung: odroid: fix an use-after-free issue for codec

[Wen Yang]

The codec variable is still being used after the of_node_put() call,
which may result in use-after-free.

Fixes: bc3cf17b575a ("ASoC: samsung: odroid: Add support for secondary CPU DAI")
Signed-off-by: Wen Yang 
Cc: Krzysztof Kozlowski 
Cc: Sangbeom Kim 
Cc: Sylwester Nawrocki 
Cc: Liam Girdwood 
Cc: Mark Brown 
Cc: Jaroslav Kysela 
Cc: Takashi Iwai 
Cc: alsa-de...@alsa-project.org
Cc: linux-kernel@vger.kernel.org
---
 sound/soc/samsung/odroid.c | 6 --
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/sound/soc/samsung/odroid.c b/sound/soc/samsung/odroid.c
index dfb6e46..64ebe89 100644
--- a/sound/soc/samsung/odroid.c
+++ b/sound/soc/samsung/odroid.c
@@ -284,9 +284,8 @@ static int odroid_audio_probe(struct platform_device *pdev)
}
 
of_node_put(cpu);
-   of_node_put(codec);
if (ret < 0)
-   return ret;
+   goto err_put_node;
 
ret = snd_soc_of_get_dai_link_codecs(dev, codec, codec_link);
if (ret < 0)
@@ -317,6 +316,7 @@ static int odroid_audio_probe(struct platform_device *pdev)
goto err_put_clk_i2s;
}
 
+   of_node_put(codec);
return 0;
 
 err_put_clk_i2s:
@@ -326,6 +326,8 @@ static int odroid_audio_probe(struct platform_device *pdev)
 err_put_cpu_dai:
of_node_put(cpu_dai);
snd_soc_of_put_dai_link_codecs(codec_link);
+err_put_node:
+   of_node_put(codec);
return ret;
 }
 
-- 
2.9.5