lkml.org 
[lkml]   [2000]   [Nov]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Modprobe local root exploit
Keith Owens writes:
> All these patches against request_module are attacking the problem at
> the wrong point. The kernel can request any module name it likes,
> using any string it likes, as long as the kernel generates the name.
> The real problem is when the kernel blindly accepts some user input and
> passes it straight to modprobe, then the kernel is acting like a setuid
> wrapper for a program that was never designed to run setuid.

Rather than add sanity checking to modprobe, it would be a lot easier
and safer from a security audit point of view to have the kernel call
/sbin/kmodprobe instead of /sbin/modprobe. Then kmodprobe can sanitise
all the data and exec the real modprobe. That way the only thing that
needs auditing is a string munging/sanitising program.

--Malcolm

--
Malcolm Beattie <mbeattie@sable.ox.ac.uk>
Unix Systems Programmer
Oxford University Computing Services
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 12:45    [W:0.093 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site