[PATCH] kunit: Fix potential null dereference in kunit_device_driver_test()

[PATCH] kunit: Fix potential null dereference in kunit_device_driver_test()

[Gax-c]

From: Zichen Xie <zichenxie0106@gmail.com>

kunit_kzalloc() may return a NULL pointer, dereferencing it without
NULL check may lead to NULL dereference.
Add a NULL check for test_state.

Fixes: d03c720e03bd ("kunit: Add APIs for managing devices")
Signed-off-by: Zichen Xie <zichenxie0106@gmail.com>
---
 lib/kunit/kunit-test.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c
index 37e02be1e710..d9c781c859fd 100644
--- a/lib/kunit/kunit-test.c
+++ b/lib/kunit/kunit-test.c
@@ -805,6 +805,8 @@ static void kunit_device_driver_test(struct kunit *test)
 	struct device *test_device;
 	struct driver_test_state *test_state = kunit_kzalloc(test, sizeof(*test_state), GFP_KERNEL);
 
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_state);
+
 	test->priv = test_state;
 	test_driver = kunit_driver_create(test, "my_driver");
 
-- 
2.34.1

Re: [PATCH] kunit: Fix potential null dereference in kunit_device_driver_test()

[Greg KH]

On Thu, Nov 14, 2024 at 11:17:46PM -0600, Gax-c wrote:
> From: Zichen Xie <zichenxie0106@gmail.com>
> 
> kunit_kzalloc() may return a NULL pointer, dereferencing it without
> NULL check may lead to NULL dereference.
> Add a NULL check for test_state.
> 
> Fixes: d03c720e03bd ("kunit: Add APIs for managing devices")
> Signed-off-by: Zichen Xie <zichenxie0106@gmail.com>
> ---
>  lib/kunit/kunit-test.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c
> index 37e02be1e710..d9c781c859fd 100644
> --- a/lib/kunit/kunit-test.c
> +++ b/lib/kunit/kunit-test.c
> @@ -805,6 +805,8 @@ static void kunit_device_driver_test(struct kunit *test)
>  	struct device *test_device;
>  	struct driver_test_state *test_state = kunit_kzalloc(test, sizeof(*test_state), GFP_KERNEL);
>  
> +	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_state);
> +
>  	test->priv = test_state;
>  	test_driver = kunit_driver_create(test, "my_driver");
>  
> -- 
> 2.34.1
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- You have marked a patch with a "Fixes:" tag for a commit that is in an
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  Documentation/process/stable-kernel-rules.rst file for how to resolve
  this.

If you wish to discuss this problem further, or you have questions about
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Greg will reply once he has dug out from the pending patches received
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thanks,

greg k-h's patch email bot