RE: [Intel-wired-lan] [PATCH v1 net-next 4/7] i40e: use scnprintf over strncpy+strncat

[Pucha, HimasekharX Reddy]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@xxxxxxxxxx> On Behalf Of Justin Stitt
> Sent: Wednesday, October 11, 2023 3:57 AM
> To: Brandeburg, Jesse <jesse.brandeburg@xxxxxxxxx>; Nguyen, Anthony L <anthony.l.nguyen@xxxxxxxxx>; David S. Miller <davem@xxxxxxxxxxxxx>; Eric Dumazet <edumazet@xxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Paolo Abeni <pabeni@xxxxxxxxxx>
> Cc: netdev@xxxxxxxxxxxxxxx; Justin Stitt <justinstitt@xxxxxxxxxx>; intel-wired-lan@xxxxxxxxxxxxxxxx; linux-hardening@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: [Intel-wired-lan] [PATCH v1 net-next 4/7] i40e: use scnprintf over strncpy+strncat
>
> `strncpy` is deprecated for use on NUL-terminated destination strings
> [1] and as such we should prefer more robust and less ambiguous string
> interfaces.
>
> Moreover, `strncat` shouldn't really be used either as per
> fortify-string.h:
>  * Do not use this function. While FORTIFY_SOURCE tries to avoid
>  * read and write overflows, this is only possible when the sizes
>  * of @p and @q are known to the compiler. Prefer building the
>  * string with formatting, via scnprintf() or similar.
>
> Instead, use `scnprintf` with "%s%s" format string. This code is now
> more readable and robust.
>
> 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>
>
> ---
> Note: build-tested only.
> ---
>  drivers/net/ethernet/intel/i40e/i40e_ddp.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
>

Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@xxxxxxxxx> (A Contingent worker at Intel)