dns.NewMsg can return nil on unsupported query types

Author: jedisct1

dnscrypt-proxy/resolve.go

@@ -24,6 +24,9 @@ func resolveQuery(server string, qName string, qType uint16, sendClientSubnet bo
 	transport.ReadTimeout = 2 * time.Second
 	client := &dns.Client{Transport: transport}
 	msg := dns.NewMsg(qName, qType)
+	if msg == nil {
+		return nil, fmt.Errorf("unsupported DNS record type: %d", qType)
+	}
 	msg.RecursionDesired = true
 	msg.Opcode = dns.OpcodeQuery
 	msg.UDPSize = uint16(MaxDNSPacketSize)

dnscrypt-proxy/xtransport.go

@@ -474,6 +474,9 @@ func (xTransport *XTransport) resolveUsingResolver(
 	defer cancel()
 	for _, rrType := range queryType {
 		msg := dns.NewMsg(fqdn(host), rrType)
+		if msg == nil {
+			continue
+		}
 		msg.RecursionDesired = true
 		msg.UDPSize = uint16(MaxDNSPacketSize)
 		msg.Security = true