(RHSA-2011:0927) 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:

• An integer overflow flaw in ib_uverbs_poll_cq() could allow a local,
  unprivileged user to cause a denial of service or escalate their
  privileges. (CVE-2010-4649, Important)

• A race condition in the way new InfiniBand connections were set up could
  allow a remote user to cause a denial of service. (CVE-2011-0695,
  Important)

• A flaw in the Stream Control Transmission Protocol (SCTP) implementation
  could allow a remote attacker to cause a denial of service if the sysctl
  “net.sctp.addip_enable” variable was turned on (it is off by default).
  (CVE-2011-1573, Important)

• Flaws in the AGPGART driver implementation when handling certain IOCTL
  commands could allow a local, unprivileged user to cause a denial of
  service or escalate their privileges. (CVE-2011-1745, CVE-2011-2022,
  Important)

• An integer overflow flaw in agp_allocate_memory() could allow a local,
  unprivileged user to cause a denial of service or escalate their
  privileges. (CVE-2011-1746, Important)

• A flaw allowed napi_reuse_skb() to be called on VLAN (virtual LAN)
  packets. An attacker on the local network could trigger this flaw by
  sending specially-crafted packets to a target system, possibly causing a
  denial of service. (CVE-2011-1576, Moderate)

• An integer signedness error in next_pidmap() could allow a local,
  unprivileged user to cause a denial of service. (CVE-2011-1593, Moderate)

• A flaw in the way the Xen hypervisor implementation handled CPUID
  instruction emulation during virtual machine exits could allow an
  unprivileged guest user to crash a guest. This only affects systems that
  have an Intel x86 processor with the Intel VT-x extension enabled.
  (CVE-2011-1936, Moderate)

• A flaw in inet_diag_bc_audit() could allow a local, unprivileged user to
  cause a denial of service (infinite loop). (CVE-2011-2213, Moderate)

• A missing initialization flaw in the XFS file system implementation
  could lead to an information leak. (CVE-2011-0711, Low)

• A flaw in ib_uverbs_poll_cq() could allow a local, unprivileged user to
  cause an information leak. (CVE-2011-1044, Low)

• A missing validation check was found in the signals implementation. A
  local, unprivileged user could use this flaw to send signals via the
  sigqueueinfo system call, with the si_code set to SI_TKILL and with spoofed
  process and user IDs, to other processes. Note: This flaw does not allow
  existing permission checks to be bypassed; signals can only be sent if your
  privileges allow you to already do so. (CVE-2011-1182, Low)

• A heap overflow flaw in the EFI GUID Partition Table (GPT) implementation
  could allow a local attacker to cause a denial of service by mounting a
  disk containing specially-crafted partition tables. (CVE-2011-1776, Low)

• Structure padding in two structures in the Bluetooth implementation
  was not initialized properly before being copied to user-space, possibly
  allowing local, unprivileged users to leak kernel stack memory to
  user-space. (CVE-2011-2492, Low)

Red Hat would like to thank Jens Kuehnel for reporting CVE-2011-0695;
Vasiliy Kulikov for reporting CVE-2011-1745, CVE-2011-2022, and
CVE-2011-1746; Ryan Sweat for reporting CVE-2011-1576; Robert Swiecki for
reporting CVE-2011-1593; Dan Rosenberg for reporting CVE-2011-2213 and
CVE-2011-0711; Julien Tinnes of the Google Security Team for reporting
CVE-2011-1182; Timo Warns for reporting CVE-2011-1776; and Marek Kroemeke
and Filip Palian for reporting CVE-2011-2492.

Bug fix documentation will be available shortly from the Technical Notes
document linked to in the References.

Users should upgrade to these updated packages, which contain backported
patches to correct these issues, and fix the bugs noted in the Technical
Notes. The system must be rebooted for this update to take effect.