kernel, perf, python security update

CentOS Errata and Security Advisory CESA-2015:1221

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

• A NULL pointer dereference flaw was found in the way the Linux kernel’s
  virtual console implementation handled reference counting when accessing
  pseudo-terminal device files (/dev/pts/*). A local, unprivileged attacker
  could use this flaw to crash the system. (CVE-2011-5321, Moderate)

• It was found that the Linux kernel’s ping socket implementation did not
  properly handle socket unhashing during spurious disconnects, which could
  lead to a use-after-free flaw. On x86-64 architecture systems, a local user
  able to create ping sockets could use this flaw to crash the system.
  On non-x86-64 architecture systems, a local user able to create ping
  sockets could use this flaw to escalate their privileges on the system.
  (CVE-2015-3636, Moderate)

• An integer overflow flaw was found in the way the Linux kernel randomized
  the stack for processes on certain 64-bit architecture systems, such as
  x86-64, causing the stack entropy to be reduced by four. (CVE-2015-1593,
  Low)

• A flaw was found in the way the Linux kernel’s 32-bit emulation
  implementation handled forking or closing of a task with an ‘int80’ entry.
  A local user could potentially use this flaw to escalate their privileges
  on the system. (CVE-2015-2830, Low)

• It was found that the Linux kernel’s TCP/IP protocol suite implementation
  for IPv6 allowed the Hop Limit value to be set to a smaller value than the
  default one. An attacker on a local network could use this flaw to prevent
  systems on that network from sending or receiving network packets.
  (CVE-2015-2922, Low)

These updated kernel packages also include numerous bug fixes and one
enhancement. Space precludes documenting all of these changes in this
advisory. For information on the most significant of these changes, users
are directed to the following article on the Red Hat Customer Portal:

https://access.redhat.com/articles/1506133

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

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2015-July/083404.html

Affected packages:
kernel
kernel-abi-whitelists
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-2015:1221