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0 pointsest313y ago0 comments

I think making it harder to build an OS by increasing its scope is not going to help people to build Linux alternatives.

As for the components, at least their interfaces are standardized. You can remove memory sticks by manufacturer A and replace them with memory sticks from manufacturer B without problem. Same goes for SATA SSDs or mice or keyboards.

Note that I'm all in favour of creating OSS firmware for devices, that's amazing. But one should not destroy the fundamental boundary between the OS and the firmware that runs the hardware.

0 comments

dist1ll3y ago

Building an OS is hard. There's no way around its complexity. But closing your eyes and pretending everything is a file is a security disaster waiting to happen (actually, happening every day).

And furthermore, OS research is not only about building Linux alternatives. There are a lot of operating systems that have a much narrower focus than full-blown multi-tenant GPOS. So building holistic systems with a narrower focus is a much more achievable goal.

> As for the components, at least their interfaces are standardized

That's not true once you step into SoC land. Components are running walled-garden firmware and binary blobs that are undocumented. There's just no incentive to provide a developer platform if no one gives a shit about holistic OSes in the first place.

GekkePrutser3y ago

> But closing your eyes and pretending everything is a file is a security disaster waiting to happen (actually, happening every day).

How so? I can see the limited access control in Linux is an issue, and for this reason augmented security MAC (Mandatory Access Control) controls exist like SELinux and AppArmor.

But I don't see how the nature of everything being a file is a vulnerability in itself.

I'd be happy to learn how though.

fanf23y ago

If you want to follow the principles of capability security, then a key part of the strategy is to eliminate “ambient authority”, that is, any kind of globally accessible way of obtaining a capability.

In traditional unix-like systems, file descriptors are very close to capabilities. But the global filesystem namespace is a source of ambient authority.

There are a couple of ways to fix this issue: fine-grained per-process namespaces like Plan 9, so that the filesystem’s authority can be attenuated as necessary, so it becomes more like a capability. Or eliminate absolute pathnames from the API, so you have to use functions like openat() to get an fd relative to an existing fd.

dist1ll3y ago

It was a lame attempt at humor, a roundabout way of referring to the simplifying assumptions that *nix systems generally make of the underlying machine.

MisterTea3y ago

> But closing your eyes and pretending everything is a file is a security disaster waiting to happen (actually, happening every day).

What is this in response to? GP never mentioned file interfaces.

Godel_unicode3y ago

Sure they did, they talked about the abstractions present in Linux.

1 more reply

simonh3y ago

> There are a lot of operating systems that have a much narrower focus than full-blown multi-tenant GPOS.

I hear some of them are used to manage embedded components in GPOS systems. Oh, wait…!

dist1ll3y ago

Narrow focus =/= only control one hardware component

j / k navigate · click thread line to collapse

0 comments

dist1ll3y ago

Building an OS is hard. There's no way around its complexity. But closing your eyes and pretending everything is a file is a security disaster waiting to happen (actually, happening every day).

> As for the components, at least their interfaces are standardized

GekkePrutser3y ago

> But closing your eyes and pretending everything is a file is a security disaster waiting to happen (actually, happening every day).

How so? I can see the limited access control in Linux is an issue, and for this reason augmented security MAC (Mandatory Access Control) controls exist like SELinux and AppArmor.

But I don't see how the nature of everything being a file is a vulnerability in itself.

I'd be happy to learn how though.

fanf23y ago

In traditional unix-like systems, file descriptors are very close to capabilities. But the global filesystem namespace is a source of ambient authority.

dist1ll3y ago

It was a lame attempt at humor, a roundabout way of referring to the simplifying assumptions that *nix systems generally make of the underlying machine.

MisterTea3y ago

> But closing your eyes and pretending everything is a file is a security disaster waiting to happen (actually, happening every day).

What is this in response to? GP never mentioned file interfaces.

Godel_unicode3y ago

Sure they did, they talked about the abstractions present in Linux.

1 more reply

simonh3y ago

> There are a lot of operating systems that have a much narrower focus than full-blown multi-tenant GPOS.

I hear some of them are used to manage embedded components in GPOS systems. Oh, wait…!

dist1ll3y ago

Narrow focus =/= only control one hardware component

j / k navigate · click thread line to collapse