Red Hat Bugzilla – Bug 169261
CVE-2005-3055 async usb devio oops
Last modified: 2007-11-30 17:07:08 EST
+++ This bug was initially created as a clone of Bug #169260 +++
Harald Welte mailed the lkml on 20050925 with a report of how to cause a local
oops if a user has permissions to access an arbitrary usb device. I've rated
this as 'moderate' instead of 'important' due to that requirement. Although usb
permissions will be given automatically to console users, a DOS from a user who
has physical access to a machine is little extra risk and we ignore that from
the severity calculation.
See the following URL for the description and patch
(See followup from Linus; proposed patch won't be applied)
I have verified that RHEL 3 does not give access by default, both before
and after X start (init 3). I have pam-0.75-58, initscripts-7.31.16.EL-1.
When usbdevfs is mounted, no extra flags are supplied.
Normally access is granted by giving options "devmode" or "devuid"
to usbdevfs, but remember that one can do use chown(1) too.
It is not persistent across reboots, but it works otherwise.
Mark wrote that permissions are given, but perhaps he meant RHEL 4
and then cloned the bug into RHEL 3. I'm going to check if I have
same userland as he did.
I am taking back the comment #3 for now. It is possible to open read-only,
so the question is if harmful ioctls are available in such case.
The discusson on vendor-sec was also mirrored to lkml; here is the link to the
most recent message (use thread previous to see the others)
This issue is on Red Hat Engineering's list of planned work items
for the upcoming Red Hat Enterprise Linux 3.8 release. Engineering
resources have been assigned and barring unforeseen circumstances, Red
Hat intends to include this item in the 3.8 release.
Created attachment 127737 [details]
Candidate #1 - Same as RHEL-4
A fix for this problem has just been committed to the RHEL3 U8
patch pool this evening (in kernel version 2.4.21-40.9.EL).
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.