(RHSA-2013:0662) 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 bugs:

• Previously, init scripts were unable to set the MAC address of the master
  interface properly because it was overwritten by the first slave MAC
  address. To avoid this problem, this update re-introduces the check for an
  unassigned MAC address before setting the MAC address of the first slave
  interface as the MAC address of the master interface. (BZ#908735)

• When using transparent proxy (TProxy) over IPv6, the kernel previously
  created neighbor entries for local interfaces and peers that were not
  reachable directly. This update corrects this problem and the kernel no
  longer creates invalid neighbor entries. (BZ#909158)

• 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#915582)

• A previously backported patch introduced usage of the page_descs length
  field but did not set the page data length for the FUSE page descriptor.
  This code path can be exercised by a loopback device (pagecache_write_end)
  if used over FUSE. As a result, fuse_copy_page does not copy page data from
  the page descriptor to the user-space request buffer and the user space can
  see uninitialized data. This could previously lead to file system data
  corruption. This problem has been fixed by setting the page_descs length
  prior to submitting the requests, and FUSE therefore provides correctly
  initialized data. (BZ#916956)

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.