worker: fix passing multiple SharedArrayBuffers at once

V8 has a handle scope below each `GetSharedArrayBufferId()` call,
so using a `v8::Local` that outlives that handle scope to store
references to `SharedArrayBuffer`s is invalid and may cause accidental
de-duplication of passed `SharedArrayBuffer`s.

Use a persistent handle instead to address this issue.

Fixes: https://github.com/nodejs/node/issues/28559

PR-URL: https://github.com/nodejs/node/pull/28582
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/test/parallel/test-worker-message-port-multiple-sharedarraybuffers.js b/test/parallel/test-worker-message-port-multiple-sharedarraybuffers.js
new file mode 100644
index 0000000000..eb68236e4d
--- /dev/null
+++ b/test/parallel/test-worker-message-port-multiple-sharedarraybuffers.js
@@ -0,0 +1,17 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const { MessageChannel } = require('worker_threads');
+
+// Regression test for https://github.com/nodejs/node/issues/28559
+
+const obj = [
+  [ new SharedArrayBuffer(0), new SharedArrayBuffer(1) ],
+  [ new SharedArrayBuffer(2), new SharedArrayBuffer(3) ]
+];
+
+const { port1, port2 } = new MessageChannel();
+port1.once('message', common.mustCall((message) => {
+  assert.deepStrictEqual(message, obj);
+}));
+port2.postMessage(obj);