TCA_BPF_FD
bpf_fd = nla_get_u32(tb[TCA_BPF_FD]);
is_ebpf = tb[TCA_BPF_FD];
[TCA_BPF_FD] = { .type = NLA_U32 },
ret = nlattr_add(req, TCA_BPF_FD, &fd, sizeof(fd));