`strncpy` is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces.
The "...-1" pattern makes it evident that netdev->name is expected to be NUL-terminated. Meanwhile, it seems NUL-padding is not required due to alloc_etherdev zero-allocating the buffer. 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. This is in line with other uses of strscpy on netdev->name: $ rg "strscpy\(netdev\->name.*pci.*" drivers/net/ethernet/intel/e1000e/netdev.c 7455: strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name)); drivers/net/ethernet/intel/ixgbe/ixgbe_main.c 10839: strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name)); 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 <justinst...@google.com> --- Note: build-tested only. --- drivers/net/ethernet/intel/e100.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/e100.c b/drivers/net/ethernet/intel/e100.c index d3fdc290937f..01f0f12035ca 100644 --- a/drivers/net/ethernet/intel/e100.c +++ b/drivers/net/ethernet/intel/e100.c @@ -2841,7 +2841,7 @@ static int e100_probe(struct pci_dev *pdev, const struct pci_device_id *ent) netdev->netdev_ops = &e100_netdev_ops; netdev->ethtool_ops = &e100_ethtool_ops; netdev->watchdog_timeo = E100_WATCHDOG_PERIOD; - strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1); + strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name)); nic = netdev_priv(netdev); netif_napi_add_weight(netdev, &nic->napi, e100_poll, E100_NAPI_WEIGHT); -- 2.42.0.609.gbb76f46606-goog
