net: atheros: 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 and dev_info():
|     dev_info(&adapter->pdev->dev,
|             "%s link is up %d Mbps %s\n",
|             netdev->name, adapter->link_speed,
|             adapter->link_duplex == FULL_DUPLEX ?
|             "full duplex" : "half duplex");

Furthermore, NUL-padding is not required as netdev is already
zero-initialized through alloc_etherdev().

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
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html
Link: https://github.com/KSPP/linux/issues/90
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20231005-strncpy-drivers-net-ethernet-atheros-atlx-atl2-c-v1-1-493f113ebfc7@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/atheros/atlx/atl2.c b/drivers/net/ethernet/atheros/atlx/atl2.c
index 1b487c071cb6281730c20f6481117cc6221e1de4..bcfc9488125b15c1dc11ec251584a9490364faa9 100644 (file)
--- a/drivers/net/ethernet/atheros/atlx/atl2.c
+++ b/drivers/net/ethernet/atheros/atlx/atl2.c
@@ -1377,7 +1377,7 @@ static int atl2_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
        netdev->watchdog_timeo = 5 * HZ;
        netdev->min_mtu = 40;
        netdev->max_mtu = ETH_DATA_LEN + VLAN_HLEN;
-       strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);
+       strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));
 
        netdev->mem_start = mmio_start;
        netdev->mem_end = mmio_start + mmio_len;