(RHSA-2009:1671) Important: kernel security and bug fix update

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

This update fixes the following security issues:

• a flaw was found in the Realtek r8169 Ethernet driver in the Linux
  kernel. pci_unmap_single() presented a memory leak that could lead to IOMMU
  space exhaustion and a system crash. An attacker on the local network could
  trigger this flaw by using jumbo frames for large amounts of network
  traffic. (CVE-2009-3613, Important)

• NULL pointer dereference flaws were found in the r128 driver in the Linux
  kernel. Checks to test if the Concurrent Command Engine state was
  initialized were missing in private IOCTL functions. An attacker could use
  these flaws to cause a local denial of service or escalate their
  privileges. (CVE-2009-3620, Important)

• an information leak was found in the Linux kernel. On AMD64 systems,
  32-bit processes could access and read certain 64-bit registers by
  temporarily switching themselves to 64-bit mode. (CVE-2009-2910, Moderate)

• the unix_stream_connect() function in the Linux kernel did not check if a
  UNIX domain socket was in the shutdown state. This could lead to a
  deadlock. A local, unprivileged user could use this flaw to cause a denial
  of service. (CVE-2009-3621, Moderate)

This update also fixes the following bugs:

• an iptables rule with the recent module and a hit count value greater
  than the ip_pkt_list_tot parameter (the default is 20), did not have any
  effect over packets, as the hit count could not be reached. (BZ#529306)

• in environments that use dual-controller storage devices with the cciss
  driver, Device-Mapper Multipath maps could not be detected and configured,
  due to the cciss driver not exporting the bus attribute via sysfs. This
  attribute is now exported. (BZ#529309)

• the kernel crashed with a divide error when a certain joystick was
  attached. (BZ#532027)

• a bug in the mptctl_do_mpt_command() function in the mpt driver may have
  resulted in crashes during boot on i386 systems with certain adapters using
  the mpt driver, and also running the hugemem kernel. (BZ#533798)

• on certain hardware, the igb driver was unable to detect link statuses
  correctly. This may have caused problems for network bonding, such as
  failover not occurring. (BZ#534105)

• the RHSA-2009:1024 update introduced a regression. After updating to Red
  Hat Enterprise Linux 4.8 and rebooting, network links often failed to be
  brought up for interfaces using the forcedeth driver. “no link during
  initialization” messages may have been logged. (BZ#534112)

• the RHSA-2009:1024 update introduced a second regression. On certain
  systems, PS/2 keyboards failed to work. (BZ#537344)

• a bug in checksum offload calculations could have crashed the bnx2x
  firmware when the iptable_nat module was loaded, causing network traffic
  to stop. (BZ#537013)

• a check has been added to the IPv4 code to make sure that the routing
  table data structure, rt, is not NULL, to help prevent future bugs in
  functions that call ip_append_data() from being exploitable. (BZ#537016)

• possible kernel pointer dereferences on systems with several NFS mounts
  (a mixture of “-o lock” and “-o nolock”), which in rare cases may have
  caused a system crash, have been resolved. (BZ#537017)

Users should upgrade to these updated packages, which contain backported
patches to correct these issues. The system must be rebooted for this
update to take effect.