(RHSA-2013:0744) Important: kernel security and bug fix update

Security:

• An integer overflow flaw, leading to a heap-based buffer overflow, was
  found in the way the Intel i915 driver in the Linux kernel handled the
  allocation of the buffer used for relocation copies. A local user with
  console access could use this flaw to cause a denial of service or escalate
  their privileges. (CVE-2013-0913, Important)

• A buffer overflow flaw was found in the way UTF-8 characters were
  converted to UTF-16 in the utf8s_to_utf16s() function of the Linux kernel’s
  FAT file system implementation. A local user able to mount a FAT file
  system with the “utf8=1” option could use this flaw to crash the system or,
  potentially, to escalate their privileges. (CVE-2013-1773, Important)

• A flaw was found in the way KVM handled guest time updates when the
  buffer the guest registered by writing to the MSR_KVM_SYSTEM_TIME machine
  state register (MSR) crossed a page boundary. A privileged guest user could
  use this flaw to crash the host or, potentially, escalate their privileges,
  allowing them to execute arbitrary code at the host kernel level.
  (CVE-2013-1796, Important)

• A potential use-after-free flaw was found in the way KVM handled guest
  time updates when the GPA (guest physical address) the guest registered by
  writing to the MSR_KVM_SYSTEM_TIME machine state register (MSR) fell into a
  movable or removable memory region of the hosting user-space process (by
  default, QEMU-KVM) on the host. If that memory region is deregistered from
  KVM using KVM_SET_USER_MEMORY_REGION and the allocated virtual memory
  reused, a privileged guest user could potentially use this flaw to
  escalate their privileges on the host. (CVE-2013-1797, Important)

• A flaw was found in the way KVM emulated IOAPIC (I/O Advanced
  Programmable Interrupt Controller). A missing validation check in the
  ioapic_read_indirect() function could allow a privileged guest user to
  crash the host, or read a substantial portion of host kernel memory.
  (CVE-2013-1798, Important)

• A race condition in install_user_keyrings(), leading to a NULL pointer
  dereference, was found in the key management facility. A local,
  unprivileged user could use this flaw to cause a denial of service.
  (CVE-2013-1792, Moderate)

• A NULL pointer dereference in the XFRM implementation could allow a local
  user who has the CAP_NET_ADMIN capability to cause a denial of service.
  (CVE-2013-1826, Moderate)

• A NULL pointer dereference in the Datagram Congestion Control Protocol
  (DCCP) implementation could allow a local user to cause a denial of
  service. (CVE-2013-1827, Moderate)

• Information leak flaws in the XFRM implementation could allow a local
  user who has the CAP_NET_ADMIN capability to leak kernel stack memory to
  user-space. (CVE-2012-6537, Low)

• Two information leak flaws in the Asynchronous Transfer Mode (ATM)
  subsystem could allow a local, unprivileged user to leak kernel stack
  memory to user-space. (CVE-2012-6546, Low)

• An information leak was found in the TUN/TAP device driver in the
  networking implementation. A local user with access to a TUN/TAP virtual
  interface could use this flaw to leak kernel stack memory to user-space.
  (CVE-2012-6547, Low)

• An information leak in the Bluetooth implementation could allow a local
  user who has the CAP_NET_ADMIN capability to leak kernel stack memory to
  user-space. (CVE-2013-0349, Low)

• A use-after-free flaw was found in the tmpfs implementation. A local user
  able to mount and unmount a tmpfs file system could use this flaw to cause
  a denial of service or, potentially, escalate their privileges.
  (CVE-2013-1767, Low)

• A NULL pointer dereference was found in the Linux kernel’s USB Inside Out
  Edgeport Serial Driver implementation. An attacker with physical access to
  a system could use this flaw to cause a denial of service. (CVE-2013-1774,
  Low)

Red Hat would like to thank Andrew Honig of Google for reporting
CVE-2013-1796, CVE-2013-1797, and CVE-2013-1798. CVE-2013-1792 was
discovered by Mateusz Guzik of Red Hat EMEA GSS SEG Team.