krustlet VS runc

Oh it’s certainly looking like that IMO.

You can run wasm in k8s: https://krustlet.dev/

Docker itself can run wasm: https://wasmlabs.dev/articles/docker-without-containers/

There are a few serverless runtimes based on wasm: https://wasmcloud.com/

A lot of those are powered by wasmtime or WasmEdge.

If you’re wanting to be able to just pull down a random app and run it as wasm, that’s inherently harder with wasm, because you have to recompile, and amazing compiling stuff is always harder than it should be. For example I compiled jq to wasm to other day, so you dont have to worry (as much) about the CVEs that was issued recently. https://github.com/rockwotj/jq-wasi

It can, kubevirt is a project for running VMs https://kubevirt.io/ and there have been more esoteric things like WASM (https://github.com/krustlet/krustlet).

Or you can run Krustlet instead of Kubelet. That makes it so you can only run WebAssembly on the cluster - so no Go, no Python, only Rust!

But the project seems to have died: https://github.com/krustlet/krustlet/graphs/contributors

There are some cloud providers that are starting to offer wasm support. Docker is currently working on wasm https://docs.docker.com/desktop/wasm/ There is also krustlet https://krustlet.dev/ which lets you run wasm in kubernetes

> If one writes Go or Rust, there are much better ways to run them than targeting WASM

wasm has its place, especially for contained workloads that can be wrapped in its strict capability boundaries (think, file-encoding jobs that shouldn't access anything else but said files: https://news.ycombinator.com/item?id=29112713).

> Containers are still the defacto standard.

wasmedge [0], atmo [1], krustlet [2], blueboat [3] and numerous other projects are turning up the heat [4]!

[0] https://github.com/WasmEdge/WasmEdge

[1] https://github.com/suborbital/atmo

[2] https://github.com/krustlet/krustlet

[3] https://github.com/losfair/blueboat

[4] https://news.ycombinator.com/item?id=30155295

I can speak to this. Containers, and by extension k8s, break a well known security boundary that has existed for a very long time - whether you are using a real (hardware) server or a virtual machine on the cloud if you pop that instance/server generally speaking you only have access to that server. Yeh, you might find a db config with connection details if you landed on say a web app host but in general you still have to work to start popping the next N servers.

That's not the case when you are running in k8s and the last container breakout was just announced ~1 month ago: https://github.com/opencontainers/runc/security/advisories/G... .

At the end of the day it is simply not a security boundary. It can solve other problems but not security ones.

It's interesting that, in light of things like this, you still see large software companies adding support for new components written in non-memory safe languages (e.g. C)

As an example Red Hat OpenShift added support for crun(https://github.com/containers/crun) this year(https://cloud.redhat.com/blog/whats-new-in-red-hat-openshift...), which is written in C as an alternative to runc, which is written in Go(https://github.com/opencontainers/runc)...

Rabbit hole indeed. That wasn't related to my job at the time, lol. The job change came with a company-provided computer and that put an end to the tinkering.

BTW, I found my hacks to make runc run on Chromebook: https://github.com/opencontainers/runc/compare/main...gabrys...

being the main author of crun, I can clarify that statement: I am not a fan of Go _for this particular use case_.

Using C instead of Go avoided a bunch of the workarounds that exists in runc to workaround the Go runtime, e.g. https://github.com/opencontainers/runc/blob/main/libcontaine...

runc

Not OP, but if I had to guess, a lot of this can be picked up by just observing common security issues in the Linux space, since similar mistakes and oversights have caused quite a few real-world CVEs in the past, e.g. this random example of a TOCTTOU vulnerability in runc.