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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"node:test aborts in InternalCallbackScope::Close after listen EPERM","articleBody":"### Version\n\nReproduced with v24.20.0 and v26.7.0.\n\n### Platform\n\nLinux 7.1.9-arch1-2 x86_64, glibc 2.44.\n\n### Subsystem\n\ntest_runner, async_hooks, platform\n\n### What steps will reproduce the bug?\n\nWhen `bind(2)` returns `EPERM` during a `node:test` test, Node can abort in `InternalCallbackScope::Close()` instead of reporting the listen error. The larger JS body appears to matter for timing. A much smaller `server.listen()` test reports `listen EPERM` normally.\n\nSave this as `deny-bind.c`:\n\n```c\n#define _GNU_SOURCE\n#include \u003cerrno.h>\n#include \u003csys/socket.h>\n\nint bind(int socket, const struct sockaddr *address, socklen_t address_len) {\n  errno = EPERM;\n  return -1;\n}\n```\n\nSave this as `repro.mjs`:\n\n```js\nimport { test } from 'node:test';\nimport assert from 'node:assert/strict';\nimport { randomUUID } from 'node:crypto';\nimport { mkdtemp, readFile, rm } from 'node:fs/promises';\nimport { join } from 'node:path';\nimport { tmpdir } from 'node:os';\nimport { createServer } from 'node:http';\nimport { spawn } from 'node:child_process';\n\nconst sourceId = randomUUID();\nconst stamp = '2026-08-30T12:00:00.000Z';\nconst item = { id: randomUUID(), version: 1, title: 'x', description: '', expected: '', steps: '', actual: '', evidence: '', author: '', team: '', area: '', feature: '', pagePath: '/reports', kind: 'issue', impact: 'high', status: 'new', priority: 'unassigned', owner: '', resolution: '', release: 'test', browser: '', viewport: '', createdAt: stamp, updatedAt: stamp, comments: [], history: [] };\nconst envelope = (changes = [{ sequence: 1, item }], overrides = {}) => ({ schemaVersion: 1, mode: 'changes', sourceId, after: 0, nextCursor: 1, hasMore: false, exportedAt: stamp, changes, ...overrides });\n\nfunction run(args, token = 'test-key'.padEnd(40, 'x')) {\n  return new Promise((resolve) => {\n    const child = spawn(process.execPath, ['-e', 'process.exit(0)', ...args], {\n      env: { ...process.env, FEEDBACK_SYNC_TOKEN: token, FEEDBACK_REMOTE_URL: '' },\n    });\n    let output = '';\n    child.stdout.on('data', (b) => { output += b; });\n    child.stderr.on('data', (b) => { output += b; });\n    child.on('close', (code) => resolve({ code, output }));\n  });\n}\n\ntest('reproducer', async () => {\n  const directory = await mkdtemp(join(tmpdir(), 'feedback-cli-'));\n  let failSecond = true;\n  let redirect = false;\n  const server = createServer((request, response) => {\n    if (redirect) { response.writeHead(302, { location: 'https://example.com' }); response.end(); return; }\n    const after = Number(new URL(request.url, 'http://localhost').searchParams.get('after'));\n    if (after === 1 && failSecond) { response.writeHead(503); response.end(); return; }\n    response.setHeader('content-type', 'application/json');\n    response.end(JSON.stringify(after === 0 ? envelope(undefined, { hasMore: true }) : after === 1 ? envelope([{ sequence: 2, item: { ...item, version: 2, status: 'planned' } }], { after: 1, nextCursor: 2 }) : envelope([], { after: 2, nextCursor: 2 })));\n  });\n  await new Promise((resolve) => server.listen(0, '127.0.0.1', resolve));\n  const url = `http://127.0.0.1:${server.address().port}`;\n  const args = ['--url', url, '--allow-http', '--out', directory];\n  try {\n    assert.equal((await run(['--url', url, '--out', directory])).code, 1);\n    assert.equal((await run(args)).code, 1);\n    assert.equal(JSON.parse(await readFile(join(directory, 'feedback.json'))).cursor, 1);\n    failSecond = false;\n    assert.equal((await run(args)).code, 0);\n    assert.equal((await run(args)).code, 0);\n    redirect = true;\n    assert.equal((await run(args)).code, 1);\n  } finally {\n    await new Promise((resolve) => server.close(resolve));\n    await rm(directory, { recursive: true, force: true });\n  }\n});\n```\n\nCompile the interceptor and run the test:\n\n```bash\ncc -shared -fPIC -o deny-bind.so deny-bind.c\nLD_PRELOAD=\"$PWD/deny-bind.so\" node --test --test-isolation=none repro.mjs\n```\n\nThis reproduced on every attempted run with both listed Node versions. It also occurs with the default process isolation, where the test child aborts and the parent reports a failed test.\n\n### How often does it reproduce? Is there a required condition?\n\nEvery run with the reproducer above on this machine. `bind()` must fail with `EPERM`. The original occurrence was inside a restricted environment where loopback binding was denied. When binding is permitted, the same test passes.\n\n### What is the expected behavior? Why is that the expected behavior?\n\nThe test runner should report `Error: listen EPERM: operation not permitted 127.0.0.1` and exit with a normal test failure. A smaller `server.listen()` test under the same interceptor already behaves this way.\n\n### What do you see instead?\n\nThe process aborts with exit status 134:\n\n```text\nAssertion failed: (env_->execution_async_id()) == (0)\n\n1: node::Assert(node::AssertionInfo const&)\n2: node::InternalCallbackScope::Close()\n3: node::InternalCallbackScope::~InternalCallbackScope()\n4: node::PerIsolatePlatformData::RunForegroundTask(...)\n5: node::PerIsolatePlatformData::FlushForegroundTasksInternal()\n6: uv_run\n7: node::SpinEventLoopInternal(node::Environment*)\n8: node::NodeMainInstance::Run()\n9: node::Start(int, char**)\n```\n\nOn v24.20.0 the assertion is at `src/api/callback.cc:165`; on v26.7.0 it is at line 185.\n\n### Additional information\n\nThis may be related to #38155, but that older case involved `async-hook-domain` monkey-patching. This reproducer uses only built-in Node modules and the test runner.\n\nNo core dump is attached because cores may contain private process memory.\n","author":{"url":"https://github.com/Fuucodi0X","@type":"Person","name":"Fuucodi0X"},"datePublished":"2026-08-30T14:34:11Z","url":"https://github.com/nodejs/node/issues/65667"}