Synopsis

Moderate: GFS-kernel security and bug fix update

Type/Severity

Security Advisory: Moderate

Topic

Updated GFS-kernel packages that fix one security issue are now available
for Red Hat Enterprise Linux 4.8, kernel release 2.6.9-89.0.20.EL.

The Red Hat Security Response Team 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 GFS-kernel packages contain modules that provide the ability to mount
and use GFS file systems.

A flaw was found in the gfs_lock() implementation. The GFS locking code
could skip the lock operation for files that have the S_ISGID bit
(set-group-ID on execution) in their mode set. A local, unprivileged user
on a system that has a GFS file system mounted could use this flaw to cause
a kernel panic. (CVE-2010-0727)

As well, these updated GFS-kernel packages are in sync with the latest
kernel (2.6.9-89.0.20.EL). The modules in earlier GFS-kernel packages fail
to load because they do not match the running kernel. It is possible to
force-load the modules; however, with this update, force-loading the
modules is not required.

Users are advised to upgrade to these latest GFS-kernel packages, which
resolve this issue and are updated for use with the 2.6.9-89.0.20.EL
kernel.

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

Affected Products

• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) 4 x86_64
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) 4 ppc
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) 4 ia64
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) 4 i386
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) - Extended Update Support resilientstorage for RHEL 4ES x86_64
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) - Extended Update Support resilientstorage for RHEL 4ES ia64
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) - Extended Update Support resilientstorage for RHEL 4ES i386
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) - Extended Update Support resilientstorage for RHEL 4AS x86_64
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) - Extended Update Support resilientstorage for RHEL 4AS ppc
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) - Extended Update Support resilientstorage for RHEL 4AS ia64
• Red Hat Enterprise Linux Resilient Storage (for RHEL Server) - Extended Update Support resilientstorage for RHEL 4AS i386

Fixes

• BZ - 570863 - CVE-2010-0727 bug in GFS/GFS2 locking code leads to dos

CVEs

• CVE-2010-0727

References

• http://www.redhat.com/security/updates/classification/#moderate

This erratum does not contain any packages.