kernel: bpf: Add BPF_PROG_TYPE_CGROUP_SKB attach type enforcement in BPF_LINK_CREATE

In the Linux kernel, the following vulnerability has been resolved: bpf: Add BPFPROGTYPECGROUPSKB attach type enforcement in BPFLINKCREATE bpfprogattach uses attachtypetoprogtype to enforce proper attach type for BPFPROGTYPECGROUPSKB. linkcreate uses bpfprogget and relies on...