_dbus_full_duplex_pipe (int        *fd1,
                        int        *fd2,
                        dbus_bool_t blocking,
                        DBusError  *error)
{
  SOCKET temp, socket1 = -1, socket2 = -1;
  struct sockaddr_in saddr;
  int len;
  u_long arg;

  _dbus_win_startup_winsock ();

  temp = socket (AF_INET, SOCK_STREAM, 0);
  if (temp == INVALID_SOCKET)
    {
      DBUS_SOCKET_SET_ERRNO ();
      goto out0;
    }

  _DBUS_ZERO (saddr);
  saddr.sin_family = AF_INET;
  saddr.sin_port = 0;
  saddr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);

  if (bind (temp, (struct sockaddr *)&saddr, sizeof (saddr)) == SOCKET_ERROR)
    {
      DBUS_SOCKET_SET_ERRNO ();
      goto out0;
    }

  if (listen (temp, 1) == SOCKET_ERROR)
    {
      DBUS_SOCKET_SET_ERRNO ();
      goto out0;
    }

  len = sizeof (saddr);
  if (getsockname (temp, (struct sockaddr *)&saddr, &len) == SOCKET_ERROR)
    {
      DBUS_SOCKET_SET_ERRNO ();
      goto out0;
    }

  socket1 = socket (AF_INET, SOCK_STREAM, 0);
  if (socket1 == INVALID_SOCKET)
    {
      DBUS_SOCKET_SET_ERRNO ();
      goto out0;
    }

  if (connect (socket1, (struct sockaddr  *)&saddr, len) == SOCKET_ERROR)
    {
      DBUS_SOCKET_SET_ERRNO ();
      goto out1;
    }

  socket2 = accept (temp, (struct sockaddr *) &saddr, &len);
  if (socket2 == INVALID_SOCKET)
    {
      DBUS_SOCKET_SET_ERRNO ();
      goto out1;
    }

  if (!blocking)
    {
      arg = 1;
      if (ioctlsocket (socket1, FIONBIO, &arg) == SOCKET_ERROR)
        {
          DBUS_SOCKET_SET_ERRNO ();
          goto out2;
        }

      arg = 1;
      if (ioctlsocket (socket2, FIONBIO, &arg) == SOCKET_ERROR)
        {
          DBUS_SOCKET_SET_ERRNO ();
          goto out2;
        }
    }

  *fd1 = socket1;
  *fd2 = socket2;

  _dbus_verbose ("full-duplex pipe %d:%d <-> %d:%d\n",
                 *fd1, socket1, *fd2, socket2);

  closesocket (temp);

  return TRUE;

out2:
  closesocket (socket2);
out1:
  closesocket (socket1);
out0:
  closesocket (temp);

  dbus_set_error (error, _dbus_error_from_errno (errno),
                  "Could not setup socket pair: %s",
                  _dbus_strerror_from_errno ());

  return FALSE;
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.