Node application on k8s fails with Assertion (slen) > (0)' failed.`

[aartek]

Hi, our node application run on kubernetes recently started failing from a weird reason. It's run on Node 10.16.3 (the same was happening on 10.15.3) and it fails with message:

node[18]: ../src/node_crypto.cc:1925:static void node::crypto::SSLWrap<Base>::GetSession(const v8::FunctionCallbackInfo<v8::Value>&) [with Base = node::TLSWrap]: Assertion `(slen) > (0)' failed.

The problem seems to be random. Application works normally and suddenly the issue occurs and it fails.

Upgrade from 10.15.3 to 10.16.3 didn't help, so I decided to ask here. Maybe you have any idea of what can be the reason of such error and how can we deal with it?

[LEQADA]

A minimal, reproducible example would be helpful.

[aartek]

It would be, but I'd need to send attach a whole app probably. This is a simple express app which periodically does some http requests, being more specific, it's a smoke-test which performs some CRUD operations on other services.

We have the same app deployed in other aws availability zones, but failures occurs only in one of them. There are over 30 restarts since I created this issue.

[bnoordhuis]

If it is caused by something in v10.16.3, then it's almost certainly caused by the upgrade from openssl 1.1.0j to 1.1.1c.

I went over the relevant code in node.js and openssl and I don't see any changes that really stand out but our handling of i2d_SSL_SESSION()'s return value looks like it could be improved anyway.

I'll open a pull request shortly. It would be nice if you could test it out.

[aartek]

@bnoordhuis I've applied these changes to 10.x tree, built the docker image, deployed, and seems that the issue disappeared. No crashes since 4h.

Are you going to make a PR to the 10.x tree?

[bnoordhuis]

Great to hear, thanks for testing. It'll be back-ported automatically to v10.x after it's been in master for a while (unless it doesn't cherry-pick cleanly, in which case I'll do it manually.)

[aartek]

@bnoordhuis, I wanted to ask if there is any progress in propagating it to v10.x? Could I get any estimated date when I could expect it to be released?

[bnoordhuis]

@aartek I can't really provide you with one, it depends on when the release team thinks it's safe to include.

The usual order of things is fix goes into master -> current (v12.x) -> lts (v10.x). LTS releases are naturally conservative and slower paced so you should expect at least one or two months from fix to release.

[richardlau]

@bnoordhuis, I wanted to ask if there is any progress in propagating it to v10.x? Could I get any estimated date when I could expect it to be released?

The current release plan is https://github.com/nodejs/Release/wiki. All dates are approximate and as mentioned above the LTS releases are slower paced so changes might not get into the next scheduled release.

cc @nodejs/lts