RHSA-2011:0836 - Security Advisory

Topic

Updated kernel packages that fix multiple security issues and various bugs
are now available for Red Hat Enterprise Linux 6.

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:

• An integer underflow flaw, leading to a buffer overflow, was found in the

Linux kernel's Datagram Congestion Control Protocol (DCCP) implementation.
This could allow a remote attacker to cause a denial of service.
(CVE-2011-1770, Important)

• Missing sanity checks were found in setup_arg_pages() in the Linux

kernel. When making the size of the argument and environment area on the
stack very large, it could trigger a BUG_ON(), resulting in a local denial
of service. (CVE-2010-3858, Moderate)

• A missing validation check was found in the bcm_release() and

raw_release() functions in the Linux kernel's Controller Area Network (CAN)
implementation. This could allow a local, unprivileged user to cause a
denial of service. (CVE-2011-1598, CVE-2011-1748, Moderate)

• The fix for Red Hat Bugzilla bug 656461, as provided in RHSA-2011:0542,

introduced a regression in the cifs_close() function in the Linux kernel's
Common Internet File System (CIFS) implementation. A local, unprivileged
user with write access to a CIFS file system could use this flaw to cause a
denial of service. (CVE-2011-1771, Moderate)

Red Hat would like to thank Dan Rosenberg for reporting CVE-2011-1770; Brad
Spengler for reporting CVE-2010-3858; and Oliver Hartkopp for reporting
CVE-2011-1748.

This update also fixes various bugs. Documentation for these bug fixes 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 resolve 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 Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• 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 Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.1 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.1 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x
• 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
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension (for IBM z Systems) 6 s390x

Fixes

• BZ - 645222 - CVE-2010-3858 kernel: setup_arg_pages: diagnose excessive argument size
• BZ - 698057 - CVE-2011-1598 CVE-2011-1748 kernel: missing check in can/bcm and can/raw socket releases
• BZ - 703011 - CVE-2011-1770 kernel: dccp: handle invalid feature options length
• BZ - 703016 - CVE-2011-1771 kernel: cifs oops when creating file with O_DIRECT set
• BZ - 704014 - [brocade 6.1 bug] bfa fc staying tech preview [rhel-6.1.z]

CVEs

• CVE-2010-3858
• CVE-2011-1748
• CVE-2011-1770
• CVE-2011-1598
• CVE-2011-1771

References

• https://access.redhat.com/security/updates/classification/#important
• https://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/6.1_Technical_Notes/kernel.html#RHSA-2011-0836