dnsutil: extractMDNSService out-of-bounds

celzero · Oct 4, 2023 · 9486a0f · 9486a0f
1 parent 0875e82
commit 9486a0f
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/intra/xdns/dnsutil.go b/intra/xdns/dnsutil.go
@@ -1049,7 +1049,7 @@ func extractMDNSDomain(qname string) (svc, tld string) {
 	tldarpa4 := strings.LastIndex(qname, arpa4suffix)
 	tldarpa6 := strings.LastIndex(qname, arpa6suffix)
 	tldlocal := strings.LastIndex(qname, localsuffix)
-	if tldlocal == len(qname)-len(localsuffix) {
+	if tldlocal > 0 && tldlocal == len(qname)-len(localsuffix) {
 		svc = qname[:tldlocal-1] // remove trailing dot; example. -> example
 		tld = localsuffix
 	} else if tldarpa4 > 0 {