code: func validateNoIPCollisions(hif HostInterfaces, hostOnlyNet *net.IPNet, currHostOnlyNets map[string]*hostOnlyNetwork) error {
  	hostOnlyByCIDR := map[string]*hostOnlyNetwork{}
  	//listHostOnlyAdapters returns a map w/ virtualbox net names as key.  Rekey to CIDRs
  	for _, n := range currHostOnlyNets {
  		ipnet := net.IPNet{IP: n.IPv4.IP, Mask: n.IPv4.Mask}
  		hostOnlyByCIDR[ipnet.String()] = n
  	}
  
  	m, err := listHostInterfaces(hif, hostOnlyByCIDR)
  	if err != nil {
  		return err
  	}
  
  	collision, err := checkIPNetCollision(hostOnlyNet, m)
  	if err != nil {
  		return err
  	}
  
  	if collision {
  		return ErrNetworkAddrCollision
  	}
  	return nil
  }
docs: // validateNoIPCollisions ensures no conflicts between the host's network interfaces and the vbox host-only network that
  // will be used for machine vm instances.