Re: [PATCH v2 02/10] kfuzztest: add user-facing API and data structures

[Alexander Potapenko]

On Fri, Sep 19, 2025 at 4:58 PM Ethan Graham <ethan.w.s.graham@xxxxxxxxx> wrote:
>
> From: Ethan Graham <ethangraham@xxxxxxxxxx>
>
> Add the foundational user-facing components for the KFuzzTest framework.
> This includes the main API header <linux/kfuzztest.h>, the Kconfig
> option to enable the feature, and the required linker script changes
> which introduce three new ELF sections in vmlinux.
>
> Note that KFuzzTest is intended strictly for debug builds only, and
> should never be enabled in a production build. The fact that it exposes
> internal kernel functions and state directly to userspace may constitute
> a serious security vulnerability if used for any reason other than
> testing.
>
> The header defines:
> - The FUZZ_TEST() macro for creating test targets.
> - The data structures required for the binary serialization format,
>   which allows passing complex inputs from userspace.
> - The metadata structures for test targets, constraints and annotations,
>   which are placed in dedicated ELF sections (.kfuzztest_*) for
>   discovery.
>
> This patch only adds the public interface and build integration; no
> runtime logic is included.
>
> Signed-off-by: Ethan Graham <ethangraham@xxxxxxxxxx>
Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx>