RHSA-2012:1347 - Security Advisory

Topic

Updated kernel packages that fix two security issues and one bug are now
available for Red Hat Enterprise Linux 5.6 Extended Update Support.

The Red Hat Security Response Team has rated this update as having
important 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 packages contain the Linux kernel, the core of any Linux
operating system.

This update fixes the following security issues:

• A flaw was found in the way socket buffers (skb) requiring TSO (TCP

segment offloading) were handled by the sfc driver. If the skb did not fit
within the minimum-size of the transmission queue, the network card could
repeatedly reset itself. A remote attacker could use this flaw to cause a
denial of service. (CVE-2012-3412, Important)

• A buffer overflow flaw was found in the hfs_bnode_read() function in the

HFS Plus (HFS+) file system implementation in the Linux kernel. A local
user able to mount a specially-crafted HFS+ file system image could use
this flaw to cause a denial of service or escalate their privileges.
(CVE-2012-2319, Low)

Red Hat would like to thank Ben Hutchings of Solarflare (tm) for reporting
CVE-2012-3412.

This update also fixes the following bug:

• Some subsystems clear the TIF_SIGPENDING flag during error handling in

fork() paths. Previously, if the flag was cleared, the ERESTARTNOINTR error
code could be returned. The underlying source code has been modified so
that the error code is no longer returned. (BZ#855754)

Users should 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/knowledge/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 for x86_64 - Extended Update Support 5.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.6 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.6 i386
• Red Hat Enterprise Linux Server - AUS 5.6 x86_64
• Red Hat Enterprise Linux Server - AUS 5.6 ia64
• Red Hat Enterprise Linux Server - AUS 5.6 i386
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 5.6 s390x
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.6 ppc
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 5.6 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 5.6 i386

Fixes

• BZ - 819471 - CVE-2012-2319 kernel: Buffer overflow in the HFS plus filesystem (different issue than CVE-2009-4020)
• BZ - 844714 - CVE-2012-3412 kernel: sfc: potential remote denial of service through TCP MSS option

CVEs

• CVE-2012-3412
• CVE-2012-2319

References

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