net: fix connect crash when call destroy in lookup handler

PR-URL: #51826
Fixes: #50841
Reviewed-By: Paolo Insogna <paolo@cowtech.it>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>

lib/net.js

@@ -1435,7 +1435,10 @@ function lookupAndConnectMultiple(
         const address = addresses[i];
         const { address: ip, family: addressType } = address;
         self.emit('lookup', err, ip, addressType, host);
-
+        // It's possible we were destroyed while looking this up.
+        if (!self.connecting) {
+          return;
+        }
         if (isIP(ip) && (addressType === 4 || addressType === 6)) {
           if (!destinations) {
             destinations = addressType === 6 ? { 6: 0, 4: 1 } : { 4: 0, 6: 1 };

test/parallel/test-destroy-socket-in-lookup.js

@@ -0,0 +1,16 @@
+'use strict';
+const common = require('../common');
+const net = require('net');
+
+// Test that the process does not crash.
+const socket = net.connect({
+  port: 12345,
+  host: 'localhost',
+  // Make sure autoSelectFamily is true
+  // so that lookupAndConnectMultiple is called.
+  autoSelectFamily: true,
+});
+// DNS resolution fails or succeeds
+socket.on('lookup', common.mustCall(() => {
+  socket.destroy();
+}));