l2tp_msgtype_print(netdissect_options *ndo, const u_char *dat)
{
	const uint16_t *ptr = (const uint16_t *)dat;

	ND_PRINT((ndo, "%s", tok2str(l2tp_msgtype2str, "MSGTYPE-#%u",
	    EXTRACT_16BITS(ptr))));
}
The software reads data past the end, or before the beginning, of the intended buffer.