(RHSA-2013:1450) 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 fix for CVE-2012-3552 released via RHSA-2012:1540
  introduced an invalid free flaw in the Linux kernel’s TCP/IP protocol suite
  implementation. A local, unprivileged user could use this flaw to corrupt
  kernel memory via crafted sendmsg() calls, allowing them to cause a denial
  of service or, potentially, escalate their privileges on the
  system. (CVE-2013-2224, Important)

• An information leak flaw was found in the way Linux kernel’s device
  mapper subsystem, under certain conditions, interpreted data written to
  snapshot block devices. An attacker could use this flaw to read data from
  disk blocks in free space, which are normally inaccessible. (CVE-2013-4299,
  Moderate)

• A format string flaw was found in the b43_do_request_fw() function in the
  Linux kernel’s b43 driver implementation. A local user who is able to
  specify the “fwpostfix” b43 module parameter could use this flaw to cause a
  denial of service or, potentially, escalate their privileges.
  (CVE-2013-2852, Low)

Red Hat would like to thank Fujitsu for reporting CVE-2013-4299, and Kees
Cook for reporting CVE-2013-2852.

This update also fixes the following bugs:

• An insufficiently designed calculation in the CPU accelerator could cause
  an arithmetic overflow in the set_cyc2ns_scale() function if the system
  uptime exceeded 208 days prior to using kexec to boot into a new
  kernel. This overflow led to a kernel panic on the systems using the Time
  Stamp Counter (TSC) clock source, primarily the systems using Intel Xeon E5
  processors that do not reset TSC on soft power cycles. A patch has been
  applied to modify the calculation so that this arithmetic overflow and
  kernel panic can no longer occur under these circumstances. (BZ#1004185)

• A race condition in the abort task and SPP device task management path of
  the isci driver could, under certain circumstances, cause the driver to
  fail cleaning up timed-out I/O requests that were pending on an SAS disk
  device. As a consequence, the kernel removed such a device from the
  system. A patch applied to the isci driver fixes this problem by sending
  the task management function request to the SAS drive anytime the abort
  function is entered and the task has not completed. The driver now cleans
  up timed-out I/O requests as expected in this situation. (BZ#1007467)

• A kernel panic could occur during path failover on systems using multiple
  iSCSI, FC or SRP paths to connect an iSCSI initiator and an iSCSI
  target. This happened because a race condition in the SCSI driver allowed
  removing a SCSI device from the system before processing its run queue,
  which led to a NULL pointer dereference. The SCSI driver has been modified
  and the race is now avoided by holding a reference to a SCSI device run
  queue while it is active. (BZ#1008507)

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.