domain AsyncHook TypeError: Cannot read properties of undefined (again)

[cemerick]

Version

v16.13.0

Platform

Linux t440p 5.4.0-89-generic #100-Ubuntu SMP Fri Sep 24 14:50:10 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

Subsystem

domain

What steps will reproduce the bug?

Fairly minimal reproduction, eval.js:

let createDomain = require("domain").create;
let vm = require("vm");

let context = vm.createContext({});
function eval(code) {
    let domain = createDomain();
    domain.run(() => {
      vm.runInContext(code, context)()
        .then(v => { console.log(v) })
        .catch(console.error);
    });
      
}
for (i = 0; i < 1000; i++) {
  eval("async () => null");
}

$ node --abort-on-uncaught-exception eval.js 
TypeError: Cannot read properties of undefined (reading 'enter')
    at AsyncHook.before (node:domain:97:20)
    at emitHook (node:internal/async_hooks:237:38)
    at emitBeforeScript (node:internal/async_hooks:503:5)
    at promiseBeforeHook (node:internal/async_hooks:347:3)
 1: 0xb02ec0 node::Abort() [node]
 2: 0xb76589  [node]
 3: 0xd4a18e  [node]
 4: 0xd4b5af v8::internal::Builtin_HandleApiCall(int, unsigned long*, v8::internal::Isolate*) [node]
 5: 0x15e7959  [node]
Aborted (core dumped)

How often does it reproduce? Is there a required condition?

The script runs without fault in node v12.22.7, but provokes failure reliably on stock node (as delivered by nvm) in versions:

• 14.18.0
• 16.13.0
• 17.1.0

Note that failure is only sporadic if the number of evaluations scheduled (the upper bound of the for loop) is cut to, say, 100 or 500, and the script runs without fault when the number is set to something very small like 10.

What is the expected behavior?

No failure, as in node v12.x.

What do you see instead?

No response

Additional information

A very similar-looking issue was reported in #30122, but the script provided here does work as expected in the failing version of node reported there (12.13.0).

[targos]

@nodejs/async_hooks

[vdeturckheim]

It seems to be a recurring issue of vm and async hooks not playing well together. I believe @Qard noticed it too.

[Qard]

As far as I can tell it's less an async_hooks issue and more an issue with domains, vm contexts, and gc timing. I don't really have the time to investigate properly right now though. 😕

[cemerick]

Having seen this failure a couple of times in production (and not wanting to use node v12.x pending an actual fix), I tinkered a bit, and found what seems like a reliable workaround: setting a dummy timeout prior to using any newly-created domain. Here's a revision of the minimal repro from the original issue description, with such a timeout added:

let createDomain = require("domain").create;
let vm = require("vm");

let context = vm.createContext({});
function eval(code) {
  let domain = createDomain();
  setTimeout(_ => {
    domain.run(() => {
      vm.runInContext(code, context)()
        .catch(console.error);
    })
  }, 0);
}

for (i = 0; i < 10000; i++) {
  eval("async () => null");
}

Whether this works because it's helping the program dodge a timing bug or not is definitely above my pay grade here, but maybe someone will find it helpful.

(Interestingly, v12 runs the above in half the time as v16. Obviously it's a pathological bit of code, but it seems notable.)