(RHSA-2014:1365) Important: kernel security and bug fix update

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

• A flaw was found in the way the Linux kernel’s futex subsystem handled
  reference counting when requeuing futexes during futex_wait(). A local,
  unprivileged user could use this flaw to zero out the reference counter of
  an inode or an mm struct that backs up the memory area of the futex, which
  could lead to a use-after-free flaw, resulting in a system crash or,
  potentially, privilege escalation. (CVE-2014-0205, Important)

The security impact of this issue was discovered by Mateusz Guzik of
Red Hat.

This update also fixes the following bugs:

• A rare race between the file system unmount code and the file system
  notification code could lead to a kernel panic. With this update, a series
  of patches has been applied to the kernel to prevent this problem.
  (BZ#1130628)

• 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#1131410)

• Later Intel CPUs added a new “Condition Changed” bit to the
  MSR_CORE_PERF_GLOBAL_STATUS register. Previously, the kernel falsely
  assumed that this bit indicates a performance interrupt, which prevented
  other NMI handlers from running and executing. To fix this problem, a
  patch has been applied to the kernel to ignore this bit in the perf code,
  enabling other NMI handlers to run. (BZ#1134695)

• Previously, certain network device drivers did not accept ethtool
  commands right after they were mounted. As a consequence, the current
  setting of the specified device driver was not applied and an error message
  was returned. The ETHTOOL_DELAY variable has been added, which makes sure
  the ethtool utility waits for some time before it tries to apply the
  options settings, thus fixing the bug. (BZ#1138300)

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.