CVE-2023-53433 net: add vlan_get_protocol_and_depth() helper

In the Linux kernel, the following vulnerability has been resolved: net: add vlangetprotocolanddepth helper Before blamed commit, pskbmaypull was used instead of skbheaderpointer in vlangetprotocol and friends. Few callers depended on skb-head being populated with MAC header, syzbot caught one of...