strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. Based on the deliberate `sizeof(dest) ... - 1` pattern we can see that both dump_info->dev_human_readable and dump_info->bus_human_readable are intended to be NUL-terminated. Moreover, since this seems to cross the file boundary let's NUL-pad to ensure no behavior change. strscpy_pad() covers both the NUL-termination and NUL-padding, let's use it. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@xxxxxxxxxxxxxxx Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx> --- Changes in v2: - prefer strscpy_pad (thanks Kees) - Link to v1: https://lore.kernel.org/r/20231017-strncpy-drivers-net-wireless-intel-iwlwifi-fw-dbg-c-v1-1-bf69ec7d1b97@xxxxxxxxxx --- Note: build-tested only. Found with: $ rg "strncpy\(" --- drivers/net/wireless/intel/iwlwifi/fw/dbg.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/fw/dbg.c b/drivers/net/wireless/intel/iwlwifi/fw/dbg.c index 3ab6a68f1e9f..7aa282592cdc 100644 --- a/drivers/net/wireless/intel/iwlwifi/fw/dbg.c +++ b/drivers/net/wireless/intel/iwlwifi/fw/dbg.c @@ -880,10 +880,10 @@ iwl_fw_error_dump_file(struct iwl_fw_runtime *fwrt, cpu_to_le32(fwrt->trans->hw_rev_step); memcpy(dump_info->fw_human_readable, fwrt->fw->human_readable, sizeof(dump_info->fw_human_readable)); - strncpy(dump_info->dev_human_readable, fwrt->trans->name, - sizeof(dump_info->dev_human_readable) - 1); - strncpy(dump_info->bus_human_readable, fwrt->dev->bus->name, - sizeof(dump_info->bus_human_readable) - 1); + strscpy_pad(dump_info->dev_human_readable, fwrt->trans->name, + sizeof(dump_info->dev_human_readable)); + strscpy_pad(dump_info->bus_human_readable, fwrt->dev->bus->name, + sizeof(dump_info->bus_human_readable)); dump_info->num_of_lmacs = fwrt->smem_cfg.num_lmacs; dump_info->lmac_err_id[0] = cpu_to_le32(fwrt->dump.lmac_err_id[0]); --- base-commit: 58720809f52779dc0f08e53e54b014209d13eebb change-id: 20231017-strncpy-drivers-net-wireless-intel-iwlwifi-fw-dbg-c-1f49f00b8a2e Best regards, -- Justin Stitt <justinstitt@xxxxxxxxxx>
