Re: [PATCH] kunit: Protect string comparisons against NULL

From: Muhammad Usama Anjum
Date: Sat Dec 30 2023 - 02:18:01 EST


On 12/20/23 8:52 PM, Richard Fitzgerald wrote:
> Add NULL checks to KUNIT_BINARY_STR_ASSERTION() so that it will fail
> cleanly if either pointer is NULL, instead of causing a NULL pointer
> dereference in the strcmp().
>
> A test failure could be that a string is unexpectedly NULL. This could
> be trapped by KUNIT_ASSERT_NOT_NULL() but that would terminate the test
> at that point. It's preferable that the KUNIT_EXPECT_STR*() macros can
> handle NULL pointers as a failure.
>
> Signed-off-by: Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>

> ---
> include/kunit/test.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/kunit/test.h b/include/kunit/test.h
> index b163b9984b33..c2ce379c329b 100644
> --- a/include/kunit/test.h
> +++ b/include/kunit/test.h
> @@ -758,7 +758,7 @@ do { \
> .right_text = #right, \
> }; \
> \
> - if (likely(strcmp(__left, __right) op 0)) \
> + if (likely((__left) && (__right) && (strcmp(__left, __right) op 0))) \
> break; \
> \
> \

--
BR,
Muhammad Usama Anjum