Linux Kernel Divide By Zero Error in ldm_get_vblks() Lets Physically Local Users Deny Service
SecurityTracker Alert ID: 1025127|
SecurityTracker URL: http://securitytracker.com/id/1025127
(Links to External Site)
Date: Feb 25 2011
Denial of service via local system|
Fix Available: Yes Vendor Confirmed: Yes |
Version(s): 2.4.x, 2.6.x|
A vulnerability was reported in the Linux Kernel. A local user can cause denial of service conditions.|
A physically local user can connect a storage device with a specially crafted LDM partition table to trigger a divide-by-zero error in the ldm_get_vblks() function in 'fs/partitions/ldm.c' and cause a kernel subsystem to crash.
The original advisory is available at:
Timo Warns (PRESENSE Technologies GmbH) reported this vulnerability.
A local user can cause a kernel subsystem to crash.|
A patch has been proposed, available at:|
Vendor URL: www.kernel.org/ (Links to External Site)
Source Message Contents
Subject: [PRE-SA-2011-01] Multiple Linux kernel vulnerabilities in partition handling code of LDM and MAC partition tables|
# PRE-CERT Security Advisory #
* Advisory: PRE-SA-2011-01
* Released on: 23 Feb 2011
* Last updated on: 23 Feb 2011
* Affected product: Linux Kernel 2.4 and 2.6
* Impact: - privilege Escalation
- disclosure of sensitive information
* Origin: storage devices
* CVE Identifier: - CVE-2011-1010
## Summary ##
Timo Warns (PRESENSE Technologies GmbH) reported some vulnerabilities in
the Linux kernel that may lead to privilege escalation,
denial-of-service, or information leakage via corrupted partition
tables. Exploiting these vulnerabilities has been demonstrated by a "USB
Stick of Death" that crashes the Linux kernel upon connecting the stick.
The kernel automatically evaluates partition tables of storage devices.
Note that this happens independently of whether auto-mounting is enabled
or not. The code for evaluating MAC and LDM partition tables contains the
A buffer overflow bug in mac_partition in fs/partitions/mac.c (for MAC
partition tables) allows to cause a denial-of-service (kernel panic)
via a corrupted MAC partition table.
For a patch, see
* A division-by-zero bug in ldm_get_vblks in fs/partitions/ldm.c (for
LDM partition tables) allows to cause a denial-of-service (kernel
oops) via a corrupted LDM partition table.
For a patch, see
* A buffer overflow bug in ldm_frag_add in fs/partitions/ldm.c (for LDM
partition tables) may allow to escalate privileges or to disclose
sensitive information via a corrupted LDM partition table.
## Workaround ##
Compile and use a kernel that does not evaluate MAC and LDM partition
tables. The corresponding configuration keys are CONFIG_MAC_PARTITION
## References ##
When further information becomes available, this advisory will be
updated. The most recent version of this advisory is available at:
## Contact ##
PRE-CERT can be reached under email@example.com. For PGP
key information, refer to http://www.pre-cert.de