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Moblin Will Run X Server As Logged-In User, Not Root
nerdyH writes "An architect of the Moblin Project has announced that Moblin 2.0 for netbooks and nettops is the first Linux distribution to run the X server as the logged-in user, rather than SUID'd to root. The fix to this decades-old security liability comes thanks to 'NRX' (No-root X) technology reportedly developed by Intel, Red Hat, and others in the X community, and the Moblin-sponsored 'Secure X' project. Besides making Linux netbooks a lot more snoop-proof, it seems like this could lead to an X-hosting renaissance of sorts, since you wouldn't be risking the whole system just to open up a specific user's account to remote X servers."
Linux's SUID X server problem has been kind of a "dirty little secret" for many years. Most modern distributions include a few crude workarounds, such as dimming the display and then freezing X whenever the user is asked to type in a root password. Getting rid of the SUID bit altogether ought to make netbooks powered by Moblin technology much more difficult to snoop on over the network.
This does not make sense. Graphical sudo wrappers have nothing to do with X being suid, and neither does anything to do with network traffic.
It seems likely that with NRX technology, you could run X apps over a network with much less risk to the app server (the system that runs the "X client" component, in the backwards terminology of X).
This is actually backwards, the only place there's less risk is for the system that the X server is running on.
I don't know how they've done it, but I know this is a good thing.
They've done it by removing the responsibility of X talking directly to the graphics hardware by implementing Kernel Mode Switching for graphics drivers (among other much needed overhauls to the Linux graphics stack). Thus X can now access what it needs at the logged-in users' level and doesn't need root.
The article repeats the common misunderstanding: "in the backwards terminology of X"
What exactly is backwards about this? X is the server, and the apps are clients.
Think about it: The client initiates the conversation with the server. The client tells the server what to do.
How is this backwards?
> Can someone spare me reading the article and let me know if DRI is still possible without root?
Yup, this whole thing rests on the new kernel modesetting. That was the last thing that required root to be able to directly frob bits on the video card. DRI also goes into the kernel as it should. The kernel is supposed to own all of the hardware and expose safe APIs for user apps to access it. For historical reasons video has been the exception to that rule. No longer.
Democrat delenda est
If graphics drivers were implemented in the kernel instead of the X server, this problem wouldn't have existed in the first place.
I just loaded it on my Eee PC and it turns the machine into a kiosk. Very unappealing for anyone who actually wants to use their netbook. Its very flashy and friendly if all you do is check your email and browse the web though.
Mr. Green