Re: [PATCH] ionic: replace deprecated strncpy with strscpy

From: Nelson, Shannon
Date: Wed Oct 11 2023 - 18:19:40 EST


On 10/11/2023 2:53 PM, 'Justin Stitt' via Pensando Drivers 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.

NUL-padding is not needed due to `ident` being memset'd to 0 just before
the copy.

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>

Thanks, I suspected this was coming soon :-)

Reviewed-by: Shannon Nelson <shannon.nelson@xxxxxxx>


---
Note: build-tested only.

Found with: $ rg "strncpy\("
---
drivers/net/ethernet/pensando/ionic/ionic_main.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_main.c b/drivers/net/ethernet/pensando/ionic/ionic_main.c
index 1dc79cecc5cc..835577392178 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_main.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_main.c
@@ -554,8 +554,8 @@ int ionic_identify(struct ionic *ionic)
memset(ident, 0, sizeof(*ident));

ident->drv.os_type = cpu_to_le32(IONIC_OS_TYPE_LINUX);
- strncpy(ident->drv.driver_ver_str, UTS_RELEASE,
- sizeof(ident->drv.driver_ver_str) - 1);
+ strscpy(ident->drv.driver_ver_str, UTS_RELEASE,
+ sizeof(ident->drv.driver_ver_str));

mutex_lock(&ionic->dev_cmd_lock);


---
base-commit: cbf3a2cb156a2c911d8f38d8247814b4c07f49a2
change-id: 20231011-strncpy-drivers-net-ethernet-pensando-ionic-ionic_main-c-709f8f1ea312

Best regards,
--
Justin Stitt <justinstitt@xxxxxxxxxx>