Important: kernel security and bug fix update

Updated kernel packages that fix several security issues and several bugs
in the Red Hat Enterprise Linux 5 kernel are now available.

This update has been rated as having important security impact by the Red
Hat Security Response Team.

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.

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied.

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/FAQ_58_10188

245777 - CVE-2007-3104 Null pointer to an inode in a dentry can cause an oops in sysfs_readdir [rhel-5.1.z]
372701 - CVE-2007-5904 Buffer overflow in CIFS VFS
396861 - CVE-2007-6206 Issue with core dump owner
412091 - [RHEL5 U1] [ia64] Kernel test failing under limited memory
414041 - NFS: System crashes trying to force umount a unresponsive, interruptible mount, which holds references to silly renamed files.
424181 - RHEL5.1 beta: System hung during warm boot-cycling test
425381 - CVE-2007-6416 [RHEL 5.2] [XEN/IA64] Security: vulnerability of copy_to_user in PAL emulation
426289 - [REG][5.1] VLAN add operation fail on s2io.ko driver(Neterion 10GbE card driver),
427994 - CVE-2007-3104 Null pointer to an inode in a dentry can cause an oops in sysfs_readdir
428791 - CVE-2008-0001 kernel: filesystem corruption by unprivileged user via directory truncation

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-3104
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-5904
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-6206
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-6416
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-0001
http://www.redhat.com/security/updates/classification/#important