Important Kernel Security Update: Red Hat Enterprise MRG RHSA-2009:0360-01

The kernel-rt packages contain the Linux kernel, the core of any Linux operating system.
These updated packages address the following security issues:
* a memory leak exists in keyctl handling. A local, unprivileged user could use this flaw to deplete kernel memory, eventually leading to a denial of service. (CVE-2009-0031, Important)
* an off-by-one underflow flaw was found in the eCryptfs subsystem. This could potentially cause a denial of service when the readlink() function returned an error. (CVE-2009-0269, Moderate)
* a deficiency was found in the Remote BIOS Update (RBU) driver for Dell systems. This could allow a local, unprivileged user to cause a denial of service by reading zero bytes from the image_type or packet_size files in "/sys/devices/platform/dell_rbu/". (CVE-2009-0322, Moderate)
* an inverted logic flaw was found in the SysKonnect FDDI PCI adapter driver, allowing driver statistics to be reset only when the CAP_NET_ADMIN capability was absent (local, unprivileged users could reset driver statistics). (CVE-2009-0675, Moderate)
* the sock_getsockopt() function in the Linux kernel did not properly initialize a data structure that can be directly returned to user-space when the getsockopt() function is called with SO_BSDCOMPAT optname set. This flaw could possibly lead to memory disclosure. (CVE-2009-0676, Moderate)
These updated packages also address numerous bugs, including the following:
* the select() and poll() functions were converted to use high resolution timers (hrtimer). Since the change, the system call pselect7() started presenting an incorrect behavior when the specified timeout was NULL. Instead of blocking until an event happened (infinite timeout) it was treated as a no timeout (zero seconds). This update fixes the problem. (BZ#487382)
* NFS is a network file system sharing technology commonly used on Linux systems. A bug exists in the Linux kernel implementation of NFS. When two (or more) clients have the same file open as it is being written to, a fault condition can arise triggering a system crash. This update resolves this bug. (BZ#486645)
* a bug affected IBM BladeCenter LS21 machines with the High Precision Event Timer (HPET) enabled in the BIOS. In these machines, the HPET_T0_CFG register booted with level-triggered interrupts (HPET_TN_LEVEL) enabled. This resulted in a boot-time hang during the delay calibration. This kernel resolves the issue by disabling HPET_TN_LEVEL when setting up periodic mode. (BZ#485428)
* Time Stamp Counter (TSC) is the preferred time source for MRG Realtime systems, although some TSC models do not comply with the requirements of a Realtime system. This kernel updates the tests carried out during boot time to check the TSC. (BZ#480244)
* under certain conditions netlink_broadcast may call yield() on behalf of a high priority kernel thread. This can lead to a system deadlock. The issue has been resolved. (BZ#463207)
Other changes included with this update are noted in the Red Hat Enterprise MRG Release Notes, 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. For this update to take effect, the system must be rebooted.