From fcc934f3d011928b89bd731b53b1a0ca54a80788 Mon Sep 17 00:00:00 2001
From: Nitzan Uziely <linkgoron@gmail.com>
Date: Sat, 20 Mar 2021 01:50:31 +0200
Subject: [PATCH] timers: fix arbitrary object clearImmediate errors

Fix errors that are caused by invoking clearImmediate
with arbitrary objects.

fixes: https://github.com/nodejs/node/issues/37806

PR-URL: https://github.com/nodejs/node/pull/37824
Fixes: https://github.com/nodejs/node/issues/37806
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
---
 lib/internal/timers.js                               |  4 ++--
 lib/timers.js                                        |  2 +-
 test/parallel/test-repl-clear-immediate-crash.js     | 12 ++++++++++++
 .../test-timers-clear-object-does-not-throw-error.js |  8 ++++++++
 4 files changed, 23 insertions(+), 3 deletions(-)
 create mode 100644 test/parallel/test-repl-clear-immediate-crash.js
 create mode 100644 test/parallel/test-timers-clear-object-does-not-throw-error.js

diff --git a/lib/internal/timers.js b/lib/internal/timers.js
index 050d356b202d70..9521c343038b4f 100644
--- a/lib/internal/timers.js
+++ b/lib/internal/timers.js
@@ -279,11 +279,11 @@ ImmediateList.prototype.append = function(item) {
 // Removes an item from the linked list, adjusting the pointers of adjacent
 // items and the linked list's head or tail pointers as necessary
 ImmediateList.prototype.remove = function(item) {
-  if (item._idleNext !== null) {
+  if (item._idleNext) {
     item._idleNext._idlePrev = item._idlePrev;
   }
 
-  if (item._idlePrev !== null) {
+  if (item._idlePrev) {
     item._idlePrev._idleNext = item._idleNext;
   }
 
diff --git a/lib/timers.js b/lib/timers.js
index 3cce2e37b007e8..73844fdbcc7613 100644
--- a/lib/timers.js
+++ b/lib/timers.js
@@ -283,7 +283,7 @@ function clearImmediate(immediate) {
     toggleImmediateRef(false);
   immediate[kRefed] = null;
 
-  if (destroyHooksExist()) {
+  if (destroyHooksExist() && immediate[async_id_symbol] !== undefined) {
     emitDestroy(immediate[async_id_symbol]);
   }
 
diff --git a/test/parallel/test-repl-clear-immediate-crash.js b/test/parallel/test-repl-clear-immediate-crash.js
new file mode 100644
index 00000000000000..ce8aaf48e7fa0e
--- /dev/null
+++ b/test/parallel/test-repl-clear-immediate-crash.js
@@ -0,0 +1,12 @@
+'use strict';
+const common = require('../common');
+const child_process = require('child_process');
+const assert = require('assert');
+
+// Regression test for https://github.com/nodejs/node/issues/37806:
+const proc = child_process.spawn(process.execPath, ['-i']);
+proc.on('error', common.mustNotCall());
+proc.on('exit', common.mustCall((code) => {
+  assert.strictEqual(code, 0);
+}));
+proc.stdin.write('clearImmediate({});\n.exit\n');
diff --git a/test/parallel/test-timers-clear-object-does-not-throw-error.js b/test/parallel/test-timers-clear-object-does-not-throw-error.js
new file mode 100644
index 00000000000000..9752f53abd0755
--- /dev/null
+++ b/test/parallel/test-timers-clear-object-does-not-throw-error.js
@@ -0,0 +1,8 @@
+'use strict';
+require('../common');
+
+// This test makes sure clearing timers with
+// objects doesn't throw
+clearImmediate({});
+clearTimeout({});
+clearInterval({});