RE: [Intel-wired-lan] [PATCH v1 net-next 7/7] igc: replace deprecated strncpy with strscpy

[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 7/7] igc: replace deprecated strncpy with strscpy
>
> `strncpy` is deprecated for use on NUL-terminated destination strings
> [1] and as such we should prefer more robust and less ambiguous string
> interfaces.
>
> We expect netdev->name to be NUL-terminated based on its use with format
> strings:
> |       if (q_vector->rx.ring && q_vector->tx.ring)
> |               sprintf(q_vector->name, "%s-TxRx-%u", netdev->name,
>
> Furthermore, we do not need NUL-padding as netdev is already
> zero-allocated:
> |       netdev = alloc_etherdev_mq(sizeof(struct igc_adapter),
> |                                  IGC_MAX_TX_QUEUES);
> ...
> alloc_etherdev() -> alloc_etherdev_mq() -> alloc_etherdev_mqs() ->
> alloc_netdev_mqs() ...
> |       p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
>
> Considering the above, a suitable replacement is `strscpy` [2] due to
> the fact that it guarantees NUL-termination on the destination buffer
> without unnecessarily NUL-padding.
>
> 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/igc/igc_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>

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