kernel security update

CentOS Errata and Security Advisory CESA-2008:1017

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

• Olaf Kirch reported a flaw in the i915 kernel driver. This flaw could,
  potentially, lead to local privilege escalation. Note: the flaw only
  affects systems based on the Intel G33 Express Chipset and newer.
  (CVE-2008-3831, Important)

• Miklos Szeredi reported a missing check for files opened with O_APPEND in
  the sys_splice(). This could allow a local, unprivileged user to bypass the
  append-only file restrictions. (CVE-2008-4554, Important)

• a deficiency was found in the Linux kernel Stream Control Transmission
  Protocol (SCTP) implementation. This could lead to a possible denial of
  service if one end of a SCTP connection did not support the AUTH extension.
  (CVE-2008-4576, Important)

In addition, these updated packages fix the following bugs:

• on Itanium® systems, when a multithreaded program was traced using the
  command “strace -f”, messages such as

  PANIC: attached pid 10740 exited
  PANIC: handle_group_exit: 10740 leader 10721
  …

will be displayed, and after which the trace would stop. With these
updated packages, “strace -f” command no longer results in these error
messages, and strace terminates normally after tracing all threads.

• on big-endian systems such as PowerPC, the getsockopt() function
  incorrectly returned 0 depending on the parameters passed to it when the
  time to live (TTL) value equaled 255.

• when using an NFSv4 file system, accessing the same file with two
  separate processes simultaneously resulted in the NFS client process
  becoming unresponsive.

• on AMD64 and Intel® 64 hypervisor-enabled systems, when a syscall
  correctly returned ‘-1’ in code compiled on Red Hat Enterprise Linux 5, the
  same code, when run with the strace utility, would incorrectly return an
  invalid return value. This has been fixed: on AMD64 and Intel® 64
  hypervisor-enabled systems, syscalls in compiled code return the same,
  correct values as syscalls run with strace.

• on the Itanium® architecture, fully-virtualized guest domains created
  using more than 64 GB of memory caused other guest domains not to receive
  interrupts. This caused soft lockups on other guests. All guest domains are
  now able to receive interrupts regardless of their allotted memory.

• when user-space used SIGIO notification, which was not disabled before
  closing a file descriptor and was then re-enabled in a different process,
  an attempt by the kernel to dereference a stale pointer led to a kernel
  crash. With this fix, such a situation no longer causes a kernel crash.

• modifications to certain pages made through a memory-mapped region could
  have been lost in cases when the NFS client needed to invalidate the page
  cache for that particular memory-mapped file.

• fully-virtualized Windows® guests became unresponsive due to the vIOSAPIC
  component being multiprocessor-unsafe. With this fix, vIOSAPIC is
  multiprocessor-safe and Windows guests do not become unresponsive.

• on certain systems, keyboard controllers could not withstand continuous
  requests to switch keyboard LEDs on or off. This resulted in some or all
  key presses not being registered by the system.

• on the Itanium® architecture, setting the “vm.nr_hugepages” sysctl
  parameter caused a kernel stack overflow resulting in a kernel panic, and
  possibly stack corruption. With this fix, setting vm.nr_hugepages works
  correctly.

• hugepages allow the Linux kernel to utilize the multiple page size
  capabilities of modern hardware architectures. In certain configurations,
  systems with large amounts of memory could fail to allocate most of this
  memory for hugepages even if it was free. This could result, for example,
  in database restart failures.

Users should upgrade to these updated packages, which contain backported
patches to correct these issues.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2008-December/077659.html
https://lists.centos.org/pipermail/centos-announce/2008-December/077660.html

Affected packages:
kernel
kernel-PAE
kernel-PAE-devel
kernel-debug
kernel-debug-devel
kernel-devel
kernel-doc
kernel-headers
kernel-xen
kernel-xen-devel

Upstream details at:
https://access.redhat.com/errata/RHSA-2008:1017