oss-sec mailing list archives

Re: CVE request: kernel: a collection of world-writable debugfs bugs


From: Vasiliy Kulikov <segoon () openwall com>
Date: Mon, 21 Mar 2011 12:21:26 +0300

On Sun, Mar 20, 2011 at 15:45 -0400, Dan Rosenberg wrote:
I don't mean to create unnecessary work, but have you actually
confirmed that exposing each of these files as world-writable actually
allows a user to cross privilege boundaries?

First 19 bugs allow anybody to interact with hardware on low level -
write to hw registers, load firmware, etc.

I'm not sure about ubifs debugfs files - they allow anybody to dump some
fs related information via printk(KERN_DEBUG, ...);  maybe it is just a
bit more precise statistics than statvfs(2) without any disclosure, but
I cannot understand it without understanding UBIFS internals.  Also this
may be not a bug in default distro setups as KERN_DEBUG messages are not
usually logged into world-readable log files.

Thanks,

-- 
Vasiliy Kulikov
http://www.openwall.com - bringing security into open computing environments


Current thread: