Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 8 Dec 2022 08:21:29 -0800
From:   Kees Cook <keescook@chromium.org>
To:     jeffxu@chromium.org
Cc:     skhan@linuxfoundation.org, akpm@linux-foundation.org,
        dmitry.torokhov@gmail.com, dverkamp@chromium.org, hughd@google.com,
        jeffxu@google.com, jorgelo@chromium.org,
        linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
        linux-mm@kvack.org, jannh@google.com,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH v6 2/6] selftests/memfd: add tests for F_SEAL_EXEC
Message-ID: <202212080818.28476A4@keescook>
References: <20221207154939.2532830-1-jeffxu@google.com>
 <20221207154939.2532830-3-jeffxu@google.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20221207154939.2532830-3-jeffxu@google.com>
Precedence: bulk

On Wed, Dec 07, 2022 at 03:49:35PM +0000, jeffxu@chromium.org wrote:
> From: Daniel Verkamp <dverkamp@chromium.org>
> 
> Basic tests to ensure that user/group/other execute bits cannot be
> changed after applying F_SEAL_EXEC to a memfd.
> 
> Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
> Co-developed-by: Jeff Xu <jeffxu@google.com>
> Signed-off-by: Jeff Xu <jeffxu@google.com>
> ---
>  tools/testing/selftests/memfd/memfd_test.c | 129 ++++++++++++++++++++-
>  1 file changed, 128 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/memfd/memfd_test.c b/tools/testing/selftests/memfd/memfd_test.c
> index 94df2692e6e4..1d7e7b36bbdd 100644
> --- a/tools/testing/selftests/memfd/memfd_test.c
> +++ b/tools/testing/selftests/memfd/memfd_test.c
> @@ -28,12 +28,44 @@
>  #define MFD_DEF_SIZE 8192
>  #define STACK_SIZE 65536
>  
> +#ifndef F_SEAL_EXEC
> +#define F_SEAL_EXEC	0x0020
> +#endif
> +
> +#ifndef MAX_PATH
> +#define MAX_PATH 256
> +#endif

I'd expect this to be named PATH_MAX, and it shouldn't need to have an
#ifdef? That's a regular POSIX define.

Otherwise, looks good. Though it'd be nice if this test use
kselftest_harness.h, but that's not your problem. :)

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook