Re: [PATCH 2/2][next] kunit/overflow: Add tests for STACK_FLEX_ARRAY_SIZE() helper

[Kees Cook <kees@kernel.org>]

On Tue, Apr 22, 2025 at 11:22:08AM -0600, Gustavo A. R. Silva wrote:
> Add a couple of tests for new STACK_FLEX_ARRAY_SIZE() helper.
> 
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
> ---
>  lib/tests/overflow_kunit.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/lib/tests/overflow_kunit.c b/lib/tests/overflow_kunit.c
> index 894691b4411a..3beb497a44be 100644
> --- a/lib/tests/overflow_kunit.c
> +++ b/lib/tests/overflow_kunit.c
> @@ -1210,6 +1210,9 @@ static void DEFINE_FLEX_test(struct kunit *test)
>  	KUNIT_EXPECT_EQ(test, __struct_size(empty->array), 0);
>  	KUNIT_EXPECT_EQ(test, __member_size(empty->array), 0);
>  
> +	KUNIT_EXPECT_EQ(test, STACK_FLEX_ARRAY_SIZE(two, array), 2);
> +	KUNIT_EXPECT_EQ(test, STACK_FLEX_ARRAY_SIZE(eight, array), 8);

Nice! Can you add a 0 test for "empty" as well?

> +
>  	/* If __counted_by is not being used, array size will have the on-stack size. */
>  	if (!IS_ENABLED(CONFIG_CC_HAS_COUNTED_BY))
>  		array_size_override = 2 * sizeof(s16);
> -- 
> 2.43.0
> 

-- 
Kees Cook