Re: [PATCH v2] net: ena: replace deprecated strncpy with strscpy

[Kees Cook]

On Thu, Dec 07, 2023 at 09:34:42PM +0000, justinstitt@xxxxxxxxxx wrote:
> `strncpy` is deprecated for use on NUL-terminated destination strings
> [1] and as such we should prefer more robust and less ambiguous string
> interfaces.
> 
> A suitable replacement is `strscpy` [2] due to the fact that it
> guarantees NUL-termination on the destination buffer without
> unnecessarily NUL-padding.
> 
> host_info allocation is done in ena_com_allocate_host_info() via
> dma_alloc_coherent() and is not zero initialized by alloc_etherdev_mq().
> 
> However zero initialization of the destination doesn't matter in this case,
> because strscpy() guarantees a NULL termination.
> 
> 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>

Yeah, this reads much better.

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-- 
Kees Cook