kernel, perf, python security update

CentOS Errata and Security Advisory CESA-2014:1724

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

Security fixes:

• A race condition flaw was found in the way the Linux kernel’s KVM
  subsystem handled PIT (Programmable Interval Timer) emulation. A guest user
  who has access to the PIT I/O ports could use this flaw to crash the host.
  (CVE-2014-3611, Important)

• A NULL pointer dereference flaw was found in the way the Linux kernel’s
  Stream Control Transmission Protocol (SCTP) implementation handled
  simultaneous connections between the same hosts. A remote attacker could
  use this flaw to crash the system. (CVE-2014-5077, Important)

• It was found that the Linux kernel’s KVM subsystem did not handle the VM
  exits gracefully for the invept (Invalidate Translations Derived from EPT)
  and invvpid (Invalidate Translations Based on VPID) instructions. On hosts
  with an Intel processor and invept/invppid VM exit support, an unprivileged
  guest user could use these instructions to crash the guest. (CVE-2014-3645,
  CVE-2014-3646, Moderate)

• A use-after-free flaw was found in the way the Linux kernel’s Advanced
  Linux Sound Architecture (ALSA) implementation handled user controls. A
  local, privileged user could use this flaw to crash the system.
  (CVE-2014-4653, Moderate)

Red Hat would like to thank Lars Bull of Google for reporting
CVE-2014-3611, and the Advanced Threat Research team at Intel Security for
reporting CVE-2014-3645 and CVE-2014-3646.

Bug fixes:

• A known issue that could prevent Chelsio adapters using the cxgb4 driver
  from being initialized on IBM POWER8 systems has been fixed. These
  adapters can now be used on IBM POWER8 systems as expected. (BZ#1130548)

• When bringing a hot-added CPU online, the kernel did not initialize a
  CPU mask properly, which could result in a kernel panic. This update
  corrects the bug by ensuring that the CPU mask is properly initialized and
  the correct NUMA node selected. (BZ#1134715)

• The kernel could fail to bring a CPU online if the hardware supported
  both, the acpi-cpufreq and intel_pstate modules. This update ensures that
  the acpi-cpufreq module is not loaded in the intel_pstate module is
  loaded. (BZ#1134716)

• Due to a bug in the time accounting of the kernel scheduler, a divide
  error could occur when hot adding a CPU. To fix this problem, the kernel
  scheduler time accounting has been reworked. (BZ#1134717)

• The kernel did not handle exceptions caused by an invalid floating point
  control (FPC) register, resulting in a kernel oops. This problem has been
  fixed by placing the label to handle these exceptions to the correct place
  in the code. (BZ#1138733)

• A previous change to the kernel for the PowerPC architecture changed
  implementation of the compat_sys_sendfile() function. Consequently, the
  64-bit sendfile() system call stopped working for files larger than 2 GB
  on PowerPC. This update restores previous behavior of sendfile() on
  PowerPC, and it again process files bigger than 2 GB as expected.
  (BZ#1139126)

• Previously, the kernel scheduler could schedule a CPU topology update
  even though the topology did not change. This could negatively affect the
  CPU load balancing, cause degradation of the system performance, and
  eventually result in a kernel oops. This problem has been fixed by
  skipping the CPU topology update if the topology has not actually changed.
  (BZ#1140300)

• Previously, recovery of a double-degraded RAID6 array could, under
  certain circumstances, result in data corruption. This could happen
  because the md driver was using an optimization that is safe to use only
  for single-degraded arrays. This update ensures that this optimization is
  skipped during the recovery of double-degraded RAID6 arrays. (BZ#1143850)

All kernel users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. The system must be
rebooted for this update to take effect.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2014-October/082872.html

Affected packages:
kernel
kernel-abi-whitelists
kernel-debug
kernel-debug-devel
kernel-devel
kernel-doc
kernel-headers
kernel-tools
kernel-tools-libs
kernel-tools-libs-devel
perf
python-perf

Upstream details at:
https://access.redhat.com/errata/RHSA-2014:1724