RHSA-2014:1959 - Security Advisory

Topic

Updated kernel packages that fix one security issue and three bugs are now
available for Red Hat Enterprise Linux 5.

Red Hat Product Security has rated this update as having Moderate security
impact. A Common Vulnerability Scoring System (CVSS) base score, which
gives a detailed severity rating, is available from the CVE link in the
References section.

Description

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

• It was found that the permission checks performed by the Linux kernel

when a netlink message was received were not sufficient. A local,
unprivileged user could potentially bypass these restrictions by passing a
netlink socket as stdout or stderr to a more privileged process and
altering the output of this process. (CVE-2014-0181, Moderate)

Red Hat would like to thank Andy Lutomirski for reporting this issue.

This update also fixes the following bugs:

• Previously, the kernel did not successfully deliver multicast packets

when the multicast querier was disabled. Consequently, the corosync utility
terminated unexpectedly and the affected storage node did not join its
intended cluster. With this update, multicast packets are delivered
properly when the multicast querier is disabled, and corosync handles the
node as expected. (BZ#902454)

• Previously, the kernel wrote the metadata contained in all system

information blocks on a single page of the /proc/sysinfo file. However,
when the machine configuration was very extensive and the data did not fit
on a single page, the system overwrote random memory regions, which in turn
caused data corruption when reading the /proc/sysconf file. With this
update, /proc/sysinfo automatically allocates a larger buffer if the data
output does not fit the current buffer, which prevents the data corruption.
(BZ#1131283)

• Prior to this update, the it_real_fn() function did not, in certain

cases, successfully acquire the SIGLOCK signal when the do_setitimer()
function used the ITIMER_REAL timer. As a consequence, the current process
entered an endless loop and became unresponsive. This update fixes the bug
and it_real_fn() no longer causes the kernel to become unresponsive.
(BZ#1134654)

All kernel users are advised to upgrade to these updated packages, which
contain backported patches 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
https://access.redhat.com/articles/11258

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

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 1094265 - CVE-2014-0181 kernel: net: insufficient permision checks of netlink messages

CVEs

• CVE-2014-0181

References

• https://access.redhat.com/security/updates/classification/#moderate