kernel, perf, python security update

CentOS Errata and Security Advisory CESA-2012:1580

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

This update fixes the following security issues:

• It was found that the RHSA-2012:0862 update did not correctly fix the
  CVE-2011-4131 issue. A malicious Network File System version 4 (NFSv4)
  server could return a crafted reply to a GETACL request, causing a denial
  of service on the client. (CVE-2012-2375, Moderate)

• A divide-by-zero flaw was found in the TCP Illinois congestion control
  algorithm implementation in the Linux kernel. If the TCP Illinois
  congestion control algorithm were in use (the sysctl
  net.ipv4.tcp_congestion_control variable set to “illinois”), a local,
  unprivileged user could trigger this flaw and cause a denial of service.
  (CVE-2012-4565, Moderate)

• A NULL pointer dereference flaw was found in the way a new node’s hot
  added memory was propagated to other nodes’ zonelists. By utilizing this
  newly added memory from one of the remaining nodes, a local, unprivileged
  user could use this flaw to cause a denial of service. (CVE-2012-5517,
  Moderate)

• It was found that the initial release of Red Hat Enterprise Linux 6 did
  not correctly fix the CVE-2009-4307 issue, a divide-by-zero flaw in the
  ext4 file system code. A local, unprivileged user with the ability to mount
  an ext4 file system could use this flaw to cause a denial of service.
  (CVE-2012-2100, Low)

• A flaw was found in the way the Linux kernel’s IPv6 implementation
  handled overlapping, fragmented IPv6 packets. A remote attacker could
  potentially use this flaw to bypass protection mechanisms (such as a
  firewall or intrusion detection system (IDS)) when sending network packets
  to a target system. (CVE-2012-4444, Low)

Red Hat would like to thank Antonios Atlasis working with Beyond Security’s
SecuriTeam Secure Disclosure program and Loganaden Velvindron of AFRINIC
for reporting CVE-2012-4444. The CVE-2012-2375 issue was discovered by Jian
Li of Red Hat, and CVE-2012-4565 was discovered by Rodrigo Freire of Red
Hat.

This update also fixes numerous bugs and adds one enhancement. Space
precludes documenting all of these changes in this advisory. Documentation
for these changes will be available shortly from the Red Hat Enterprise
Linux 6.3 Technical Notes document linked to in the References section.

Users should upgrade to these updated packages, which contain backported
patches to correct these issues, fix these bugs and add the enhancement
noted in the Technical Notes. The system must be rebooted for this update
to take effect.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2012-December/081201.html

Affected packages:
kernel
kernel-debug
kernel-debug-devel
kernel-devel
kernel-doc
kernel-firmware
kernel-headers
perf
python-perf

Upstream details at:
https://access.redhat.com/errata/RHSA-2012:1580