Re: [PATCH] crypto: cavium/nitrox - refactor deprecated strncpy

From: Kees Cook
Date: Thu Sep 14 2023 - 23:38:33 EST


On Wed, Sep 13, 2023 at 12:32:31AM +0000, Justin Stitt wrote:
> `strncpy` is deprecated for use on NUL-terminated destination strings [1].
>
> We know `hw.partname` is supposed to be NUL-terminated by its later use with seq_printf:
> | nitrox_debugfs.c +25
> | seq_printf(s, " Part Name: %s\n", ndev->hw.partname);
>
> Let's prefer a more robust and less ambiguous string interface.
>
> A suitable replacement is `strscpy` [2] due to the fact that it guarantees
> NUL-termination on the destination buffer.
>
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
> Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
> Link: https://github.com/KSPP/linux/issues/90
> Cc: linux-hardening@xxxxxxxxxxxxxxx
> Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx>

Looks correct to me.

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

--
Kees Cook