RHSA-2012:0116 - Security Advisory

Topic

Updated kernel packages that fix various security issues and several bugs
are now available for Red Hat Enterprise Linux 6.1 Extended Update Support.

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

This update fixes the following security issues:

• The proc file system could allow a local, unprivileged user to obtain

sensitive information or possibly cause integrity issues. (CVE-2011-1020,
Moderate)

• Non-member VLAN (virtual LAN) packet handling for interfaces in

promiscuous mode and also using the be2net driver could allow an attacker
on the local network to cause a denial of service. (CVE-2011-3347,
Moderate)

• A missing validation flaw was found in the Linux kernel's m_stop()

implementation. A local, unprivileged user could use this flaw to trigger
a denial of service. (CVE-2011-3637, Moderate)

• A flaw was found in the Linux kernel in the way splitting two extents in

ext4_ext_convert_to_initialized() worked. A local, unprivileged user with
the ability to mount and unmount ext4 file systems could use this flaw to
cause a denial of service. (CVE-2011-3638, Moderate)

• A NULL pointer dereference flaw was found in the way the Linux kernel's

key management facility handled user-defined key types. A local,
unprivileged user could use the keyctl utility to cause a denial of
service. (CVE-2011-4110, Moderate)

Red Hat would like to thank Kees Cook for reporting CVE-2011-1020; Somnath
Kotur for reporting CVE-2011-3347; and Zheng Liu for reporting
CVE-2011-3638.

This update also fixes several bugs. Documentation for these changes will
be available shortly from the Technical Notes document linked to in the
References section.

Users should upgrade to these updated packages, which contain backported
patches to correct these issues, and fix the bugs noted in the Technical
Notes. 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/kb/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

• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 i386
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.1 s390x
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.1 ppc64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 i386
• Red Hat Virtual Storage Appliance (from RHUI) 6.1 x86_64

Fixes

• BZ - 680358 - CVE-2011-1020 kernel: no access restrictions of /proc/pid/* after setuid program exec
• BZ - 736425 - CVE-2011-3347 kernel: be2net: promiscuous mode and non-member VLAN packets DoS
• BZ - 747848 - CVE-2011-3637 kernel: proc: fix oops on invalid /proc/<pid>/maps access
• BZ - 747942 - CVE-2011-3638 kernel: ext4: ext4_ext_insert_extent() kernel oops
• BZ - 751297 - CVE-2011-4110 kernel: keys: NULL pointer deref in the user-defined key type

CVEs

• CVE-2011-1020
• CVE-2011-3347
• CVE-2011-4110
• CVE-2011-3638

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/6.1_Technical_Notes/kernel.html#RHSA-2012-0116