Synopsis

Moderate: kernel-rt security and bug fix update

Type/Severity

Security Advisory: Moderate

Topic

Updated kernel-rt packages that fix multiple security issues and upgrade
the kernel-rt kernel to version 2.6.33.7-rt29 are now available for Red Hat
Enterprise MRG 1.3.

The Red Hat Security Response Team has rated this update as having moderate
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.

Description

The kernel-rt packages contain the Linux kernel, the core of any Linux
operating system.

This update fixes the following security issues:

• On AMD64 systems, it was discovered that the kernel did not ensure the

ELF interpreter was available before making a call to the SET_PERSONALITY
macro. A local attacker could use this flaw to cause a denial of service by
running a 32-bit application that attempts to execute a 64-bit application.
(CVE-2010-0307, Moderate)

• Information leak flaws were found in the Linux kernel Traffic Control

Unit implementation. A local attacker could use these flaws to cause the
kernel to leak kernel memory to user-space, possibly leading to the
disclosure of sensitive information. (CVE-2010-2942, Moderate)

• It was found that wireless drivers might not always clear allocated

buffers when handling a driver-specific IOCTL information request. A local
user could trigger this flaw to cause kernel memory to leak from the heap
to user-space, leading to an information leak. (CVE-2010-2955, Moderate)

• A flaw was found in the eql_g_master_cfg() function in the Linux kernel

equalizer load-balancer for serial network interfaces implementation. A
data structure in eql_g_master_cfg() was not initialized properly before
being copied to user-space. A local, unprivileged user could use this flaw
to cause an information leak. (CVE-2010-3297, Moderate)

Red Hat would like to thank Mathias Krause for reporting CVE-2010-0307, and
Dan Rosenberg for reporting CVE-2010-3297.

This update also fixes the following bugs:

• The mkinitrd utility reported the following warning message when creating

an initial ramdisk:

No module dm-mem-cache found for kernel [version], aborting.

This was caused by an erroneous dependency on dmraid-related modules. This
update removes these dependencies with the result that mkinitrd does not
issue a spurious warning about the dm-mem-cache module not being found.
(BZ#482753)

• The ibm_rtl kernel module now performs more exhaustive checking to ensure

it only loads on correct IBM hardware. (BZ#612275)

• The realtime Linux kernel has been upgraded to upstream version

2.6.33.7-rt29, which provides a number of bug fixes and enhancements for
Red Hat Enterprise MRG 1.3. (BZ#638672)

Users should upgrade to these updated packages, which upgrade the kernel-rt
kernel to version 2.6.33.7-rt29 to correct these issues. The system must be
rebooted for this update to take effect.

Solution

Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

To install kernel packages manually, use "rpm -ivh [package]". Do not
use "rpm -Uvh" as that will remove the running kernel binaries from
your system. You may use "rpm -e" to remove old kernels after
determining that the new kernel functions properly on your system.

Affected Products

• MRG Realtime 1 x86_64
• MRG Realtime 1 i386

Fixes

• BZ - 482753 - mkinitrd erroneously inserts dependencies to dm-mem-cache (not present on MRG)
• BZ - 560547 - CVE-2010-0307 kernel: DoS on x86_64
• BZ - 612275 - WARNING: at arch/x86/mm/ioremap.c:148 __ioremap_caller+0x160/0x30e()
• BZ - 624903 - CVE-2010-2942 kernel: net sched: fix some kernel memory leaks
• BZ - 628434 - CVE-2010-2955 kernel: wireless: fix 64K kernel heap content leak via ioctl
• BZ - 633145 - CVE-2010-3297 kernel: drivers/net/eql.c: reading uninitialized stack memory
• BZ - 638672 - Need to move the MRG RT source base to upstream RT (2.6.33)

CVEs

• CVE-2010-0307
• CVE-2010-2942
• CVE-2010-2955
• CVE-2010-3297

References