I'm trying to upgrade the library to the latest version available to see if the leak is resolved but I run into the following issue when a DNS request is made:
```
ipmap.go:369: W ipmap: Add: e...
> core.CloseOp() may close a net.UDPConn immediately.
For full duplex TCP, it closes read on one end, write on the other. No way to do so for UDP?
> Deadlines are used to "generate" timeout e...
> Does firestack close a pair of net.Conn in one goroutine and guarantee that these two net.Conn are not closed until another forwarding goroutine stops
I think so. `conntracker.Untrack` *should...