CVE-2026-80738 bpf: Check sk_state before sk_protocol in bpf_tcp_*_syncookie

In the Linux kernel, the following vulnerability has been resolved: bpf: Check skstate before skprotocol in bpftcpsyncookie bpftcpgensyncookie and bpftcpchecksyncookie accept a socket pointer 'sk' with argument type ARGPTRTOBTFIDSOCKCOMMON. However, they access sk-skprotocol without validating...