skb_entail
void skb_entail(struct sock *sk, struct sk_buff *skb, int flags);
skb_entail(sk, skb, ULPCB_FLAG_NO_HDR | ULPCB_FLAG_NO_APPEND);
skb_entail(sk, skb,
skb_entail(sk, skb, ULPCB_FLAG_NEED_HDR);
skb_entail(sk, skb, ULPCB_FLAG_NEED_HDR);