panic when timeout

[wolf-joe]

time="2022-12-22T03:40:12+08:00" level=warning msg="group clean call DNSCaller<223.5.5.5:53/udp> failed: read udp 192.168.1.10:44390->223.5.5.5:53: i/o timeout"
time="2022-12-22T03:40:12+08:00" level=info answer=nil cost=2006ms group=_clean q_type=AAAA question=xxx. remote="127.0.0.1:47836"
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x48 pc=0x758664]

goroutine 86050 [running]:
github.com/wolf-joe/ts-dns/redirector.(*cidrRedirector).Redirect(0xc0001a6000, 0xc00046bdd0, 0x0, 0x5, 0xc00012c1a8)
	/home/worker/git/ts-dns/redirector/redirector.go:93 +0x44
github.com/wolf-joe/ts-dns/redirector.NewRedirector.func1(0x880940, 0xc000121180, 0xc00046bdd0, 0x0, 0x0, 0x0)
	/home/worker/git/ts-dns/redirector/redirector.go:55 +0xca
github.com/wolf-joe/ts-dns/inbound.(*handlerImpl).handle(0xc000128410, 0x8808e8, 0xc0000b8300, 0xc00046bdd0, 0x0)
	/home/worker/git/ts-dns/inbound/handler.go:244 +0x475
github.com/wolf-joe/ts-dns/inbound.(*handlerImpl).ServeDNS(0xc000128410, 0x8808e8, 0xc0000b8300, 0xc00046bdd0)
	/home/worker/git/ts-dns/inbound/handler.go:149 +0x4d
github.com/wolf-joe/ts-dns/inbound.(*handlerWrapper).ServeDNS(0xc000102058, 0x8808e8, 0xc0000b8300, 0xc00046bdd0)
	/home/worker/git/ts-dns/inbound/handler.go:71 +0x4c
github.com/miekg/dns.(*Server).serveDNS(0xc00052e000, 0xc0001ba600, 0x29, 0x200, 0xc0000b8300)
	/home/worker/go/pkg/mod/github.com/miekg/[email protected]/server.go:659 +0x2fd
github.com/miekg/dns.(*Server).serveUDPPacket(0xc00052e000, 0xc000673200, 0xc0001ba600, 0x29, 0x200, 0x87e8a8, 0xc0004c4008, 0xc000676ea0, 0x0, 0x0)
	/home/worker/go/pkg/mod/github.com/miekg/[email protected]/server.go:603 +0x125
created by github.com/miekg/dns.(*Server).serveUDP
	/home/worker/go/pkg/mod/github.com/miekg/[email protected]/server.go:533 +0x395