(RHSA-2013:0661) Important: kernel security and bug fix update

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

This update fixes the following security issue:

• A race condition was found in the way the Linux kernel’s ptrace
  implementation handled PTRACE_SETREGS requests when the debuggee was woken
  due to a SIGKILL signal instead of being stopped. A local, unprivileged
  user could use this flaw to escalate their privileges. (CVE-2013-0871,
  Important)

This update also fixes the following bug:

• Due to the incorrect validation of a pointer dereference in the
  d_validate() function, running a command such as ls or find on the
  MultiVersion File System (MVFS), used by IBM Rational ClearCase, for
  example, could trigger a kernel panic. This update modifies d_validate() to
  verify the parent-child dentry relationship by searching through the
  parent’s d_child list. The kernel no longer panics in this situation.
  (BZ#915580)

Users should upgrade to these updated packages, which contain backported
patches to resolve these issues. The system must be rebooted for this
update to take effect.