Incoming TCP connections should not be added to the descriptor table until they're accept()ed

[stevenengler]

When a listening socket receives a SYN packet, it immediately registers a new socket in the descriptor table.

shadow/src/main/host/descriptor/tcp.c

Lines 1931 to 1945 in 138b84a

	switch(tcp->state) {
	case TCPS_LISTEN: {
	/* receive SYN, send SYNACK, move to SYNRECEIVED */
	if(header->flags & PTCP_SYN) {
	MAGIC_ASSERT(tcp->server);
	flags |= TCP_PF_PROCESSED;
	/* we need to multiplex a new child */
	guint64 recvBufSize = host_getConfiguredRecvBufSize(host);
	guint64 sendBufSize = host_getConfiguredSendBufSize(host);
	TCP* multiplexed = tcp_new(host, recvBufSize, sendBufSize);
	process_registerLegacyDescriptor(
	descriptor_getOwnerProcess((LegacyDescriptor*)tcp),
	(LegacyDescriptor*)multiplexed);

Shadow should wait and only register the socket in the descriptor table once the user space process calls accept().