Goroutine Leak ConnectVerfication() -> Limitter

[awerqo]

When invoke ConnectVerfication() func in runner it creates new limiter on line 717

naabu/v2/pkg/runner/runner.go

Lines 714 to 717 in 10f5605

	func (r *Runner) ConnectVerification() {
	r.scanner.ListenHandler.Phase.Set(scan.Scan)
	var swg sync.WaitGroup
	limiter := ratelimit.New(context.Background(), uint(r.options.Rate), time.Second)

Creating new instances of Limiter starts new goroutine:
https://github.com/projectdiscovery/ratelimit/blob/77dad731f2e9a2e98564787086ade7be2ac33b4e/ratelimit.go#L112-L129

And it closed only if any of two contexts done https://github.com/projectdiscovery/ratelimit/blob/main/ratelimit.go#L39-L45

select {
case <-ctx.Done():
	// Internal Context
	imiter.ticker.Stop()
	eturn
case <-limiter.ctx.Done():
	limiter.ticker.Stop()
	return
case ...

So this happens if original context done or if we call stop method https://github.com/projectdiscovery/ratelimit/blob/77dad731f2e9a2e98564787086ade7be2ac33b4e/ratelimit.go#L101-L106 that cancel second, created context https://github.com/projectdiscovery/ratelimit/blob/77dad731f2e9a2e98564787086ade7be2ac33b4e/ratelimit.go#L113

As we can see, when we invoke ConnectVerification() it creates new instance of limiter with context.Background() and not invoke Stop() later:

naabu/v2/pkg/runner/runner.go

Lines 717 to 733 in 10f5605

	limiter := ratelimit.New(context.Background(), uint(r.options.Rate), time.Second)
	verifiedResult := result.NewResult()
	for hostResult := range r.scanner.ScanResults.GetIPsPorts() {
	limiter.Take()
	swg.Add(1)
	go func(hostResult *result.HostResult) {
	defer swg.Done()
	results := r.scanner.ConnectVerify(hostResult.IP, hostResult.Ports)
	verifiedResult.SetPorts(hostResult.IP, results)
	}(hostResult)
	}
	r.scanner.ScanResults = verifiedResult
	swg.Wait()

So, we leak goroutine every ConnectVerification() call, what sometimes creates problems if we work with naabu in SDK mode

Thanks

[awerqo]

I can send a pr if it is convenient for you. It looks like it is safe to call limiter.Stop() after waiting for the swg