Re: [PATCH v4] EDAC/mc_sysfs: refactor deprecated strncpy

Kees Cook
2023-09-24T02:52:04Z

On Mon, Sep 18, 2023 at 07:47:29AM +0000, Justin Stitt wrote:
> `strncpy` is deprecated for use on NUL-terminated destination strings [1].
>
> We've already calculated bounds, possible truncation with '\0' or '\n'
> and manually NUL-terminated. The situation is now just a literal byte
> copy from one buffer to another, let's treat it as such and use a less
> ambiguous interface in memcpy.
>
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
> Link: https://github.com/KSPP/linux/issues/90
> Cc: linux-hardening@vger.kernel.org
> Signed-off-by: Justin Stitt <justinstitt@google.com>

Yeah, I think this looks good now. If a v5 is needed, a tiny improvement
would be to update the Subject: to "...: replace strncpy with memcpy".

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

-Kees

--
Kees Cook