* Re: [PATCH] net: ax88796c: replace deprecated strncpy with strscpy
2023-10-05 1:06 ` [PATCH] net: ax88796c: replace deprecated strncpy with strscpy Justin Stitt
@ 2023-10-05 4:55 ` Kees Cook
2023-10-05 8:40 ` Lukasz Stelmach
2023-10-06 23:00 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: Kees Cook @ 2023-10-05 4:55 UTC (permalink / raw)
To: Justin Stitt
Cc: Łukasz Stelmach, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni, netdev, linux-kernel,
linux-hardening
On Thu, Oct 05, 2023 at 01:06:26AM +0000, Justin Stitt 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.
>
> It should be noted that there doesn't currently exist a bug here as
> DRV_NAME is a small string literal which means no overread bugs are
> present.
>
> Also to note, other ethernet drivers are using strscpy in a similar
> pattern:
> | dec/tulip/tulip_core.c
> | 861: strscpy(info->driver, DRV_NAME, sizeof(info->driver));
> |
> | 8390/ax88796.c
> | 582: strscpy(info->driver, DRV_NAME, sizeof(info->driver));
> |
> | dec/tulip/dmfe.c
> | 1077: strscpy(info->driver, DRV_NAME, sizeof(info->driver));
> |
> | 8390/etherh.c
> | 558: strscpy(info->driver, DRV_NAME, sizeof(info->driver));
>
> 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@vger.kernel.org
> Signed-off-by: Justin Stitt <justinstitt@google.com>
Yeah, this looks like the others.
Reviewed-by: Kees Cook <keescook@chromium.org>
--
Kees Cook
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] net: ax88796c: replace deprecated strncpy with strscpy
2023-10-05 1:06 ` [PATCH] net: ax88796c: replace deprecated strncpy with strscpy Justin Stitt
2023-10-05 4:55 ` Kees Cook
@ 2023-10-05 8:40 ` Lukasz Stelmach
2023-10-06 23:00 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: Lukasz Stelmach @ 2023-10-05 8:40 UTC (permalink / raw)
To: Justin Stitt
Cc: David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
netdev, linux-kernel, linux-hardening
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It was <2023-10-05 czw 01:06>, when Justin Stitt 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.
>
> It should be noted that there doesn't currently exist a bug here as
> DRV_NAME is a small string literal which means no overread bugs are
> present.
>
> Also to note, other ethernet drivers are using strscpy in a similar
> pattern:
> | dec/tulip/tulip_core.c
> | 861: strscpy(info->driver, DRV_NAME, sizeof(info->driver));
> |
> | 8390/ax88796.c
> | 582: strscpy(info->driver, DRV_NAME, sizeof(info->driver));
> |
> | dec/tulip/dmfe.c
> | 1077: strscpy(info->driver, DRV_NAME, sizeof(info->driver));
> |
> | 8390/etherh.c
> | 558: strscpy(info->driver, DRV_NAME, sizeof(info->driver));
>
> 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@vger.kernel.org
> Signed-off-by: Justin Stitt <justinstitt@google.com>
> ---
> Note: build-tested only.
> ---
> drivers/net/ethernet/asix/ax88796c_ioctl.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
Reviewed-by: Lukasz Stelmach <l.stelmach@samsung.com>
> diff --git a/drivers/net/ethernet/asix/ax88796c_ioctl.c b/drivers/net/ethernet/asix/ax88796c_ioctl.c
> index 916ae380a004..7d2fe2e5af92 100644
> --- a/drivers/net/ethernet/asix/ax88796c_ioctl.c
> +++ b/drivers/net/ethernet/asix/ax88796c_ioctl.c
> @@ -24,7 +24,7 @@ static void
> ax88796c_get_drvinfo(struct net_device *ndev, struct ethtool_drvinfo *info)
> {
> /* Inherit standard device info */
> - strncpy(info->driver, DRV_NAME, sizeof(info->driver));
> + strscpy(info->driver, DRV_NAME, sizeof(info->driver));
> }
>
> static u32 ax88796c_get_msglevel(struct net_device *ndev)
>
> ---
> base-commit: cbf3a2cb156a2c911d8f38d8247814b4c07f49a2
> change-id: 20231005-strncpy-drivers-net-ethernet-asix-ax88796c_ioctl-c-56af20b7d992
>
> Best regards,
> --
> Justin Stitt <justinstitt@google.com>
>
>
>
--
Łukasz Stelmach
Samsung R&D Institute Poland
Samsung Electronics
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^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] net: ax88796c: replace deprecated strncpy with strscpy
2023-10-05 1:06 ` [PATCH] net: ax88796c: replace deprecated strncpy with strscpy Justin Stitt
2023-10-05 4:55 ` Kees Cook
2023-10-05 8:40 ` Lukasz Stelmach
@ 2023-10-06 23:00 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: patchwork-bot+netdevbpf @ 2023-10-06 23:00 UTC (permalink / raw)
To: Justin Stitt
Cc: l.stelmach, davem, edumazet, kuba, pabeni, netdev, linux-kernel,
linux-hardening
Hello:
This patch was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:
On Thu, 05 Oct 2023 01:06:26 +0000 you 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.
>
> [...]
Here is the summary with links:
- net: ax88796c: replace deprecated strncpy with strscpy
https://git.kernel.org/netdev/net-next/c/9c9e3ab20f35
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 4+ messages in thread