Home page logo

bugtraq logo Bugtraq mailing list archives

Re: Wmmon under FreeBSD
From: ajax () LINWORTH ORG (Ajax)
Date: Tue, 21 Dec 1999 15:35:34 -0500

On Tue, 21 Dec 1999, Steve Reid wrote:

Wmmon is a popular program for monitoring CPU load and other system
utilization. It runs as a dockapp under WindowMaker.

The FreeBSD version of this program has a feature that can be trivially
exploited to gain group kmem in recent installs, or user root in really
old installs. This affects the FreeBSD version because under FreeBSD the
program must be installed setgid kmem or setuid root in order to access
system load information through the memory devices. The Linux version
should not be vulnerable because it reads information through procfs
which requires no special privileges.

An alternative solution would be to read such information from kernfs,
usually (although optionally) mounted at /kern.  kernfs is the *bsd
equivalent to many of the files in linux's /proc.  This would, of
course, require the app to be rewritten to use /kern instead of
/dev/kmem, but well worth it in my opinion.

I should like to know why more apps don't require the *bsd {proc,kern}fs
interface.  They were, after all, designed to reduce the need for read
access to /dev/kmem.

.a.j.a.x. @ vxgas.linworth.org
"You can run Java applets from anyone, anywhere, in complete safety"
    - Charles L. Perkins, "Teach Yourself Java in 21 Days"
 3:24PM  up 83 days,  8:26, 1 user, load averages: 0.09, 0.10, 0.08

  By Date           By Thread  

Current thread:
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]