Re: [PATCH] autofs: use flexible array in ioctl structure

Kees Cook <[email protected]> Tue, 23 May 2023 10:06:10 -0700

Newsgroups	org.kernel.vger.autofs,org.kernel.vger.linux-doc,org.kernel.vger.linux-kernel,org.kernel.vger.stable
Message-ID	<[email protected]>

On Tue, 23 May 2023 10:19:35 +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <[email protected]>
> 
> Commit df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") introduced a warning
> for the autofs_dev_ioctl structure:
> 
> In function 'check_name',
>     inlined from 'validate_dev_ioctl' at fs/autofs/dev-ioctl.c:131:9,
>     inlined from '_autofs_dev_ioctl' at fs/autofs/dev-ioctl.c:624:8:
> fs/autofs/dev-ioctl.c:33:14: error: 'strchr' reading 1 or more bytes from a region of size 0 [-Werror=stringop-overread]
>    33 |         if (!strchr(name, '/'))
>       |              ^~~~~~~~~~~~~~~~~
> In file included from include/linux/auto_dev-ioctl.h:10,
>                  from fs/autofs/autofs_i.h:10,
>                  from fs/autofs/dev-ioctl.c:14:
> include/uapi/linux/auto_dev-ioctl.h: In function '_autofs_dev_ioctl':
> include/uapi/linux/auto_dev-ioctl.h:112:14: note: source object 'path' of size 0
>   112 |         char path[0];
>       |              ^~~~
> 
> [...]

Applied to for-next/hardening, thanks!

[1/1] autofs: use flexible array in ioctl structure
      https://git.kernel.org/kees/c/e6d6886d469f

-- 
Kees Cook