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@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20231018-strncpy-drivers-net-wireless-ti-wlcore-main-c-v1-1-1b1055f482a1@google.com
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