CVE-2023-54240 net: ethernet: mtk_eth_soc: fix possible NULL pointer dereference in mtk_hwlro_get_fdir_all()

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: mtkethsoc: fix possible NULL pointer dereference in mtkhwlrogetfdirall rulelocs is allocated in ethtoolgetrxnfc and the size is determined by rulecnt from user space. So rulecnt needs to be check before using...