Hi, why in sock_alloc_send_skb(sk, length+hh_len+15,0,flags&MSG_DONTWAIT, &err) 15 is added to the length of the the data of the socket. Here length=data_len+ip_hdr+udp_hdr all we need is hrd_hdr ie hh_len which is being added here, why that 15 is needed? Sourav - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/