7.6 - RHSA-2012:1426

Problem Description:

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

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.

2. Relevant releases/architectures:

Red Hat Enterprise Linux Desktop (v. 6) - i386, noarch, x86_64 Red Hat Enterprise Linux Desktop Optional (v. 6) - i386, x86_64 Red Hat Enterprise Linux HPC Node (v. 6) - noarch, x86_64 Red Hat Enterprise Linux HPC Node Optional (v. 6) - x86_64 Red Hat Enterprise Linux Server (v. 6) - i386, noarch, ppc64, s390x, x86_64 Red Hat Enterprise Linux Server Optional (v. 6) - i386, ppc64, s390x, x86_64 Red Hat Enterprise Linux Workstation (v. 6) - i386, noarch, x86_64 Red Hat Enterprise Linux Workstation Optional (v. 6) - i386, x86_64

3. Description:

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

This update fixes the following security issues:

* A use-after-free flaw was found in the Linux kernel's memory management subsystem in the way quota handling for huge pages was performed. A local, unprivileged user could use this flaw to cause a denial of service or, potentially, escalate their privileges. (CVE-2012-2133, Moderate)

* A use-after-free flaw was found in the madvise() system call implementation in the Linux kernel. A local, unprivileged user could use this flaw to cause a denial of service or, potentially, escalate their privileges. (CVE-2012-3511, Moderate)

* It was found that when running a 32-bit binary that uses a large number of shared libraries, one of the libraries would always be loaded at a predictable address in memory. An attacker could use this flaw to bypass the Address Space Layout Randomization (ASLR) security feature. (CVE-2012-1568, Low)

* Buffer overflow flaws were found in the udf_load_logicalvol() function in the Universal Disk Format (UDF) file system implementation in the Linux kernel. An attacker with physical access to a system could use these flaws to cause a denial of service or escalate their privileges. (CVE-2012-3400, Low)

Red Hat would like to thank Shachar Raindel for reporting CVE-2012-2133.

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.

4. 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.

5. Bugs fixed (http://bugzilla.redhat.com/):

804947 - CVE-2012-1568 kernel: execshield: predictable ascii armour base address 817430 - CVE-2012-2133 kernel: use after free bug in "quota" handling 843139 - CVE-2012-3400 kernel: udf: buffer overflow when parsing sparing table 849734 - CVE-2012-3511 kernel: mm: use-after-free in madvise_remove() 860787 - [xfs/xfstests 273] heavy cp workload hang [rhel-6.3.z]