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Gentoo Tesla – T2 Edition

su-tesla.space

111–120 of 154 posts

Re: Gentoo Tesla – T2 Edition

#111

Earlier quoted context omitted.

Sensible cars have a device bridging high and low security networks, forwarding data from one to the other, specifically so that a misbehaving media device or light system can't clobber the brakes or ECU. No idea if the Tesla does this or not, but it's a fairly standard approach.

Yes, it has a gateway between the high level stuff and the low level stuff. It's fairly secure too. You can't just make calls to the can bus all willy-nilly either.

> You can't just make calls to the can bus all willy-nilly either.

What do you mean by that? I would think that once you get UID=0 nothing can stop you from doing whatever you want to that device.

Re: Gentoo Tesla – T2 Edition

#112
I would love to buy a car with only FOSS software or at least source available software available inside. In the long run, I think it would be much safer than the status quo and with everything becoming computer-driven.

I've thought about doing something like this with my center nav, but it deals with setting the time on the mirror among other things. Still, I can't get updated maps without paying the dealer a few hundred dollars to put a cd in it. I end up just using openStreetMaps on my rooted phone. This is a sad state of things. It feels like a feature-phone. Hopefully the future is brighter.

Re: Gentoo Tesla – T2 Edition

#113

Earlier quoted context omitted.

How is that handled?

This is part of the Magnuson Moss Warranty Act: https://en.wikipedia.org/wiki/Magnuson%E2%80%93Moss_Warranty... In effect, the manufacturer can only deny warranty claims for a specific part iff the consumer's aftermarket repair/modifications were responsible for the warrantied part failing. i.e. "I tinted the windows, and now the brakes are failing" does not result in warranty claims on the brakes being denied. Howev…

While I appreciate the sentiment there, that seems like its ripe for protracted litigation (which will never benefit the consumer).

Plus, in a connected car situation, its going to be very difficult to prove that one thing didn't cause another.

Because you rooted the media control system, your unapproved software had the ability to speak to the brake control system and apply more-than-designed force to the brakes and thereby caused this damage.

Could you be forced into proving a negative?

That said, I think most of these things happen in the context of class action suits. In a class action, its going to be hard to blame or exclude the 1% of the class that has rooted their car.

Re: Gentoo Tesla – T2 Edition

#115

Earlier quoted context omitted.

Yes, it has a gateway between the high level stuff and the low level stuff. It's fairly secure too. You can't just make calls to the can bus all willy-nilly either.

> You can't just make calls to the can bus all willy-nilly either. What do you mean by that? I would think that once you get UID=0 nothing can stop you from doing whatever you want to that device.

there is a gateway between the media center canbus and the critical canbus. the gateway buffers all the data from the critical canbus and rate limits any requests for data which isn't broadcast regularly on the critical canbus.

You would have to get UID=0 on the canbus gateway to make requests 'willy nilly' on the critical canbus. Having UID=0 on the media centre would only help in making willy nilly requests to the gateway.

edit: clarity

Re: Gentoo Tesla – T2 Edition

#116

Earlier quoted context omitted.

Yes, it has a gateway between the high level stuff and the low level stuff. It's fairly secure too. You can't just make calls to the can bus all willy-nilly either.

> You can't just make calls to the can bus all willy-nilly either. What do you mean by that? I would think that once you get UID=0 nothing can stop you from doing whatever you want to that device.

It's a completely different computer—compare it to your typical web browser/web server model. The media computer can request display the battery information (the browser can get a list of products) but it cannot hit the accelerator (the browser cannot read other users' personal information). Even if you have root on the media center (your laptop), that doesn't make it so you can run any and all commands on the computer that regulates steering and acceleration (the web server).

Re: Gentoo Tesla – T2 Edition

#117

Earlier quoted context omitted.

It's just a chroot. Thats far less dangerous than completely reflashing it etc

So what happens when your app hits an infinite loop and locks the CPU? Or trashes some memory it shouldn't? Does autopilot still work? Do the airbags still deploy? Does the brake still work?

Preemptive multitasking means that infinite loops in userland software do not lock the CPU. Everything that anyone would cal an app is run on a system that does preemptive multitasking, so it is not a problem. Presumably, the dashboard console computer is separate from the many other computers in the car for reliability purposes. If it is not, Telsa Motors would have really messed up.

Re: Gentoo Tesla – T2 Edition

#118

Earlier quoted context omitted.

There have actually been a ton of examples over the years of researchers hacking into car systems wirelessly, some of which used the media system as the attack vector. Even if the media subsystem is running on dedicated hardware, the fact that it's networked with the rest of the car means that there's still a risk of it being used to gain access to other components.

Which is worse, proprietary closed system from car manufacturer or OSS system. There's as many pros on one side as cons on the other.

False dichotomy - I think it should be similar to Kerckhoffs's principle in the long run. OSS yes, but it's signed and audited when it's able to run. Maybe like an open source version of microcode updates for CPUs. You could file a pull request because you spotted a bug but you can't fuck around your car (bad, but not so bad) and other cars (very bad).

If the Toyota code would be public we'd hear a lot of guys screaming and if you own the car and have the knowledge I guess you are keen on looking. Sure lots of noise for manufactures and likely new attack vectors but in the end public universities could look at it. On the other hand you'll end up with OpenSSL for cars.

However it should be still safe when public that what should be the design goal. However what you read about embedded stuff in cars and airplanes...OSS would be likely an improvement. I for one would like to file a pull request against the A380 firmware :)

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