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Linux 2.4.24 Release Fixes Root Vulnerability
diegocgteleline.es writes "Linux Kernel 2.4.24 has been released and is available on kernel.org. It seems there's a bug in the mremap(2) system call, where a local user can get root privileges.The new version has been released only with the most important bugs fixed - the rest of the changes have been postponed (those changes include the XFS filesystem)."
For the Microsoft trolls to pick this one up.
Is this just more proof that Linux was built by amateurs? Or wait - I know - that Linux can't be trusted because the source code is open.
Now, for those who think I'm serious, think about it for a moment. Slashdot hypes up every single MS vulnerability as "proof" that MS systems are inherently insecure. And I wouldn't disagree that MS systems are insecure. But discovering a single (or a few) vulnerability doesn't make an OS insecure.
What it comes down to is vigilance and design. The numerous security holes in MS products are a result of bad design, not merely a mistake or two. And this is the big difference between this vulnerability - a mere isolated mistake - and Microsoft's complete lack of engineering which ensures that their software _will_ have security holes.
Okay, flame away Microsofties!
The society for a thought-free internet welcomes you.
XFS is also the X font server.....
Uh, right. "make bzImage" actually takes a couple minutes on any decently fast computer. You don't need to rebuild all the modules, and even that will take much less than an hour unless you're running ancient hardware.
LOAD "SIG",8,1
Holes like elevation of privileges (like this one) cannot be used by worms since they work only when you already have access to the system. So while these bugs are bad enough, they are still not nearly as bad as the Win-RPC, or the bugs that allowed Nimda, CodeRed etc. to exist.
Having written Windows software for years, I can tell that if local exploits ever become a concern for Windows (e.g. if Windows ever goes multiuser in a big way, where a local user may want to exploit the machine), almost every Windows application will have big problems with local exploits
...are pretty much only for convienience, that is to keep user settings and such separate among a group of mutually trusted users (like say, a family). There's not much in terms of real security.
That users created at install time default to admins with no passwords only goes to prove that even more. Which is fine, as long as a) noone unauthorized can get to the machine and b) all the users trust eachother.
On the other hand, local exploits are a grave concern in many settings, say for example a university where each student has a local account. So they should by no means be taken lightly, even if they don't produce worms.
Kjella
Live today, because you never know what tomorrow brings
Software is written by humans, and humans make errors, so software has bugs.
All software.
The sysadmin motto (abridged) is 'all software sucks, all hardware sucks'
I just looked through the bugtraq archives, and found 3 local root exploits for OpenBSD in the year 2003. That's the same class of problem as was found in Linux.
Security is a mindset, and a practice. It's not a platform.
Zapman
$ man nice
On kernel 2.4 and earlier, you usually gave the X-server a negative nice-value to give it higher priority which lead to somewhat better responsivness. But the 2.6-kernel has a new rewritten scheduler (?) that detects if the process is interactive or not and handle them differently to make interactive apps more responsive while giving non-interactive apps more throughput. By renicing the X-server you foul the kernel to not make use of this and thus get a much less responsive X desktop.
If you just compiled and installed the 2.6 kernel on a 2.4 distro that is not 2.6-ready you'll have to mock with the X startup-scripts to remove the nice/renice-stuff to make use of the great 2.6 desktop-features.
My other account has a 3-digit UID.