On Wed, Oct 18, 2023 at 09:50:01PM +0000, Justin Stitt 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. > > We expect fw_version strings to be NUL-terminated based on other similar > assignments: > > wireless/broadcom/brcm80211/brcmsmac/main.c > 7867: snprintf(wlc->wiphy->fw_version, > 7868: sizeof(wlc->wiphy->fw_version), "%u.%u", rev, patch); > > wireless/broadcom/b43legacy/main.c > 1765: snprintf(wiphy->fw_version, sizeof(wiphy->fw_version), "%u.%u", > > wireless/broadcom/b43/main.c > 2730: snprintf(wiphy->fw_version, sizeof(wiphy->fw_version), "%u.%u", > > wireless/intel/iwlwifi/dvm/main.c > 1465: snprintf(priv->hw->wiphy->fw_version, > 1466: sizeof(priv->hw->wiphy->fw_version), > > wireless/intel/ipw2x00/ipw2100.c > 5905: snprintf(info->fw_version, sizeof(info->fw_version), "%s:%d:%s", > > Based on this, NUL-padding is not required. > > 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> More clear replacements. Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> -- Kees Cook
