[PATCH] liquidio: replace deprecated strncpy with strscpy

Justin Stitt
2023-10-05T21:55:10Z

`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 required as rep_cfg is memset to 0:
| memset(&rep_cfg, 0, sizeof(rep_cfg));

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@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
---
Note: build-tested only.
---
drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c b/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
index 600de587d7a9..aa6c0dfb6f1c 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
@@ -638,7 +638,8 @@ lio_vf_rep_netdev_event(struct notifier_block *nb,
memset(&rep_cfg, 0, sizeof(rep_cfg));
rep_cfg.req_type = LIO_VF_REP_REQ_DEVNAME;
rep_cfg.ifidx = vf_rep->ifidx;
- strncpy(rep_cfg.rep_name.name, ndev->name, LIO_IF_NAME_SIZE);
+ strscpy(rep_cfg.rep_name.name, ndev->name,
+ sizeof(rep_cfg.rep_name.name));

ret = lio_vf_rep_send_soft_command(oct, &rep_cfg,
sizeof(rep_cfg), NULL, 0);

---
base-commit: cbf3a2cb156a2c911d8f38d8247814b4c07f49a2
change-id: 20231005-strncpy-drivers-net-ethernet-cavium-liquidio-lio_vf_rep-c-b23567b42939

Best regards,
--
Justin Stitt <justinstitt@google.com>