(RHSA-2015:0803) Important: kernel security and bug fix update

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

• It was found that the Linux kernel’s Infiniband subsystem did not
  properly sanitize input parameters while registering memory regions from
  user space via the (u)verbs API. A local user with access to a
  /dev/infiniband/uverbsX device could use this flaw to crash the system or,
  potentially, escalate their privileges on the system. (CVE-2014-8159,
  Important)

• An integer overflow flaw was found in the way the Linux kernel’s Frame
  Buffer device implementation mapped kernel memory to user space via the
  mmap syscall. A local user able to access a frame buffer device file
  (/dev/fb*) could possibly use this flaw to escalate their privileges on the
  system. (CVE-2013-2596, Important)

• It was found that the parse_rock_ridge_inode_internal() function of the
  Linux kernel’s ISOFS implementation did not correctly check relocated
  directories when processing Rock Ridge child link (CL) tags. An attacker
  with physical access to the system could use a specially crafted ISO image
  to crash the system or, potentially, escalate their privileges on the
  system. (CVE-2014-5471, CVE-2014-5472, Low)

Red Hat would like to thank Mellanox for reporting the CVE-2014-8159 issue.

This update also fixes the following bugs:

• The kernel could sometimes panic due to a possible division by zero in
  the kernel scheduler. This bug has been fixed by defining a new div64_ul()
  division function and correcting the affected calculation in the
  proc_sched_show_task() function. (BZ#1199898)

• When repeating a Coordinated Universal Time (UTC) value during a leap
  second (when the UTC time should be 23:59:60), the International Atomic
  Time (TAI) timescale previously stopped as the kernel NTP code incremented
  the TAI offset one second too late. A patch has been provided, which fixes
  the bug by incrementing the offset during the leap second itself. Now, the
  correct TAI is set during the leap second. (BZ#1201672)

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.