(RHSA-2009:0009) Important: kernel security and bug fix update

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

These updated packages address the following security issues:

• Tavis Ormandy discovered a deficiency in the Linux kernel 32-bit and
  64-bit emulation. This could allow a local, unprivileged user to prepare
  and run a specially-crafted binary which would use this deficiency to leak
  uninitialized and potentially sensitive data. (CVE-2008-0598, Important)

• Olaf Kirch reported a flaw in the i915 kernel driver that only affects
  the Intel G33 series and newer. This flaw could, potentially, lead to local
  privilege escalation. (CVE-2008-3831, Important)

• Miklos Szeredi reported a missing check for files opened with O_APPEND in
  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)

• Wei Yongjun reported a flaw in the Linux kernel SCTP implementation. In
  certain code paths, sctp_sf_violation_paramlen() could be called with a
  wrong parameter data type. This could lead to a possible denial of service.
  (CVE-2008-4618, Important)

• when fput() was called to close a socket, the __scm_destroy() function in
  the Linux kernel could make indirect recursive calls to itself. This could,
  potentially, lead to a denial of service issue. (CVE-2008-5029, Important)

• the ext2 and ext3 filesystem code failed to properly handle corrupted
  data structures, leading to a possible local denial of service issue when
  read or write operations were performed. (CVE-2008-3528, Low)

These updated packages also address numerous bugs, including the following:

• several System on Chip (SoC) audio drivers allocated memory in the
  platform device probe function but did not free this memory in the event of
  an error. Instead, the memory was freed in the device probe function’s
  error path. This could result in a ‘double free’ error. With this update,
  errors cause memory to be freed correctly.

• when a check was made to see if the netlink attribute fitted into
  available memory, the value returned, “remaining”, could become negative
  due to alignment in nla_next(). GCC set “remaining” to unsigned when
  testing against the sizeof(*nla), however. As a consequence, the test would
  always succeed and the function nla_for_each_attr() could, potentially,
  access memory outside the received buffer. With this update, sizeof is cast
  to an integer, ensuring sizeof(*nla) does a signed test and prevents an
  illegal memory de-reference.

• if a user-space process used a SIGIO notification and did not disable it
  before closing the file descriptor, a stale pointer was left in the
  async_queue of the real-time clock. When a different user-space process
  subsequently used a SIGIO notification, the kernel de-referenced this
  pointer and crashed. With this updated kernel, SIGIO notifications are
  disabled when the file descriptor is closed, preventing this.

• the real-time kernel included with Red Hat Enterprise Linux MRG did not
  randomize exec, heap or libc addresses. This update corrects this omission:
  exec, heap and libc addresses are now randomized.

Numerous other bug fixes included with this update are noted in the Red Hat
Enterprise MRG 1.0 Real Time Security Update Release Note, available at the
location noted in the References section below.

All Red Hat Enterprise MRG users should install this update which addresses
these vulnerabilities and fixes these bugs.