From 9150c63f4fea68a87b1873af891c0ff5dcfcb360 Mon Sep 17 00:00:00 2001
From: theanarkh <theratliter@gmail.com>
Date: Sat, 2 Mar 2024 03:09:07 +0800
Subject: [PATCH] lib: return directly if udp socket close before lookup

PR-URL: https://github.com/nodejs/node/pull/51914
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Paolo Insogna <paolo@cowtech.it>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
---
 lib/dgram.js                                  |  6 +++---
 ...t-dgram-bind-socket-close-before-lookup.js | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+), 3 deletions(-)
 create mode 100644 test/parallel/test-dgram-bind-socket-close-before-lookup.js

diff --git a/lib/dgram.js b/lib/dgram.js
index 8c8da1ad8856b5..969f696b9e50da 100644
--- a/lib/dgram.js
+++ b/lib/dgram.js
@@ -328,6 +328,9 @@ Socket.prototype.bind = function(port_, address_ /* , callback */) {
 
   // Resolve address first
   state.handle.lookup(address, (err, ip) => {
+    if (!state.handle)
+      return; // Handle has been closed in the mean time
+
     if (err) {
       state.bindState = BIND_STATE_UNBOUND;
       this.emit('error', err);
@@ -356,9 +359,6 @@ Socket.prototype.bind = function(port_, address_ /* , callback */) {
         this.emit('error', ex);
       });
     } else {
-      if (!state.handle)
-        return; // Handle has been closed in the mean time
-
       const err = state.handle.bind(ip, port || 0, flags);
       if (err) {
         const ex = new ExceptionWithHostPort(err, 'bind', ip, port);
diff --git a/test/parallel/test-dgram-bind-socket-close-before-lookup.js b/test/parallel/test-dgram-bind-socket-close-before-lookup.js
new file mode 100644
index 00000000000000..96ca71c3deeb4e
--- /dev/null
+++ b/test/parallel/test-dgram-bind-socket-close-before-lookup.js
@@ -0,0 +1,19 @@
+'use strict';
+const common = require('../common');
+const dgram = require('dgram');
+
+// Do not emit error event in callback which is called by lookup when socket is closed
+const socket = dgram.createSocket({
+  type: 'udp4',
+  lookup: (...args) => {
+    // Call lookup callback after 1s
+    setTimeout(() => {
+      args.at(-1)(new Error('an error'));
+    }, 1000);
+  }
+});
+
+socket.on('error', common.mustNotCall());
+socket.bind(12345, 'localhost');
+// Close the socket before calling DNS lookup callback
+socket.close();