kernel security update

CentOS Errata and Security Advisory CESA-2008:0089

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

These new kernel packages fix the following security issues:

A flaw was found in the virtual filesystem (VFS). An unprivileged local
user could truncate directories to which they had write permission; this
could render the contents of the directory inaccessible. (CVE-2008-0001,
Important)

A flaw was found in the Xen PAL emulation on Intel 64 platforms. A guest
Hardware-assisted virtual machine (HVM) could read the arbitrary physical
memory of the host system, which could make information available to
unauthorized users. (CVE-2007-6416, Important)

A flaw was found in the way core dump files were created. If a local user
can get a root-owned process to dump a core file into a directory, which
the user has write access to, they could gain read access to that core
file, potentially containing sensitive information. (CVE-2007-6206, Moderate)

A buffer overflow flaw was found in the CIFS virtual file system. A
remote,authenticated user could issue a request that could lead to a denial
of service. (CVE-2007-5904, Moderate)

A flaw was found in the “sysfs_readdir” function. A local user could create
a race condition which would cause a denial of service (kernel oops).
(CVE-2007-3104, Moderate)

As well, these updated packages fix the following bugs:

• running the “strace -f” command caused strace to hang, without displaying
  information about child processes.

• unmounting an unresponsive, interruptable NFS mount, for example, one
  mounted with the “intr” option, may have caused a system crash.

• a bug in the s2io.ko driver prevented VLAN devices from being added.
  Attempting to add a device to a VLAN, for example, running the “vconfig
  add [device-name] [vlan-id]” command caused vconfig to fail.

• tux used an incorrect open flag bit. This caused problems when building
  packages in a chroot environment, such as mock, which is used by the koji
  build system.

Red Hat Enterprise Linux 5 users are advised to upgrade to these updated
packages, which contain backported patches to resolve these issues.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2008-January/076801.html
https://lists.centos.org/pipermail/centos-announce/2008-January/076802.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-2008:0089