Assertion `(write_req_.result) >= (0)' failed

[kyrylkov]

Version

v16.10.0

Platform

Linux af87af56-9877-4f08-60c5-f271 5.4.0-84-generic #94~18.04.1-Ubuntu SMP Thu Aug 26 23:17:46 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

Subsystem

No response

What steps will reproduce the bug?

Running our server app with node --trace-event-categories v8,node,node.async_hooks,node.promises.rejections flags.

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

When node.promises.rejections enabled, server crashes at least once per hour with this error.

What is the expected behavior?

Printing promise rejection trace, when rejection occurs.

What do you see instead?

Node crashes

node[137]: ../src/tracing/node_trace_writer.cc:196:void node::tracing::NodeTraceWriter::AfterWrite(): Assertion `(write_req_.result) >= (0)' failed.
1: 0x5578c3cff280 node::Abort() [node]
2: 0x5578c3cff314  [node]
3: 0x5578c3e1a654  [node]
4: 0x5578c487db64  [node]
5: 0x5578c48834f6  [node]
6: 0x5578c489749d  [node]
7: 0x5578c4883e2a uv_run [node]
8: 0x7fe3b1e9f6db  [/lib/x86_64-linux-gnu/libpthread.so.0]
9: 0x7fe3b1bc871f clone [/lib/x86_64-linux-gnu/libc.so.6]
Aborted

Additional information

No response

[aduh95]

I'm not able to reproduce:

$ node --trace-event-categories v8,node,node.async_hooks,node.promises.rejections       
Welcome to Node.js v16.10.0.
Type ".help" for more information.
> 

The REPL opens as expected. Are you running some other code or some other options to get to the crash you described?

[kyrylkov]

Sorry I wansn't clear enough. That's the crash we get when we running our server app that has uncaught promise rejections with node.promises.rejections. We've added --trace-event-categories flag to get more information, but Node started crashing. It didn't seem to crash before, without the flag, but we will double check.

[kyrylkov]

Confirmed. Crash occurs only with --trace-event-categories node.promises.rejections

[aduh95]

Any chance you would be able to share a code snippet that reproduces the issue? It's almost impossible to reliably fix the issue without a repro case.

[kyrylkov]

The issue is that we don't know ourselves what code is responsible. When we add unhandledRejection listener, we get these:

Unhandled rejection at: {}
Reason: Error: Client network socket disconnected before secure TLS connection was established

As you see reason comes as an empty object. We hoped to get more details with tracing, but it just crashes.