Synopsis

Important: qemu-kvm-rhev, qemu-kvm-rhev-tools, qemu-img-rhev security and bug fix update

Type/Severity

Security Advisory: Important

Topic

Updated qemu-kvm-rhev, qemu-kvm-rhev-tools, and qemu-img-rhev packages are
now available.

The Red Hat Security Response Team has rated this update as having
important security impact. A Common Vulnerability Scoring System (CVSS)
base score, which gives a detailed severity rating, is available from the
CVE link in the References section.

Description

KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems. The qemu-kvm-rhev package provides the
user-space component for running virtual machines using KVM, in
environments managed by Red Hat Enterprise Virtualization Manager.

A buffer overflow flaw was found in the way QEMU processed the SCSI "REPORT
LUNS" command when more than 256 LUNs were specified for a single SCSI
target. A privileged guest user could use this flaw to corrupt QEMU process
memory on the host, which could potentially result in arbitrary code
execution on the host with the privileges of the QEMU process.
(CVE-2013-4344)

This issue was discovered by Asias He of Red Hat.

This update fixes the following bugs:

• In QMP monitor, if an attempt was made to create an image with the same
  file name as the backing file, an error was generated, but no message was
  displayed. Performing this action in QMP Monitor now generates the same
  error message as performing the action in HMP: "Error: Trying to create an
  image with the same file name as the backing file". (BZ#877240)
  
• QEMU I/O throttling has been disabled in Red Hat Enterprise Linux and is
  now only available enabled in the Red Hat Enterprise Virtualization QEMU
  package (qemu-kvm-rhev). (BZ#975468)
  
• When booting a guest machine, it would still boot when specifying iops
  and bps as a negative value, without displaying an error message. This has
  been fixed so that if a negative value is used the guest does not boot and
  QEMU exits with the following message 'bps and iops values must be 0 or
  greater'. (BZ#987725)
  
• When booting a guest with QMP server, hot plug was failing. It can now do
  hotplug with QEMU I/O throttling including iops, iops_wr, iops_rd, bps,
  bps_wr, bps_rd inofs successfully. (BZ#987745)
  
• Due to a change in virtualization features, all fixes and errata related
  to Red Hat Enterprise Virtualization specific features, can only be posted
  to the Red Hat Enterprise Virtualization channel. Therefore a Red Hat
  Enterprise Virtualization specific qemu-kvm (for RHEV-H-6.5.0 Errata) was
  developed. This meant that the qemu-kvm-rhev binary was mapped to a Red Had
  enterprise Virtualization channel, entitled to Red Hat Enterprise
  Virtualization customers, and disabled from the Red Hat Enterprise Linux
  channel. (BZ#997032)
  
• The qemu-kvm-rhev package now contains /usr/lib64/qemu, as this directory
  is where CEPH packages provide librbd to be used by QEMU at runtime.
  (BZ#999705)
  
• QEMU performed a core dump when iops.bps was set to a negative value.
  This has been fixed so that it no longer performs a core dump when a
  negative value is entered, instead an error message is displayed indicating
  the values must be zero of greater. (BZ#1001436)
  
• When running the "rpm -V qemu-kvm-rhev" command, an error was generated
  stating there were unsatisfied dependencies. This has been fixed so there
  now are no unsatisfied dependencies and it executes correctly. (BZ#1010930)
  

In addition, this update adds the following enhancements:

• QEMU I/O throttling allows for finer control of the rate of I/O
  operations at the QEMU level, and is therefore independent of the
  underlying storage device. A similar feature can be created by using
  cgroups at the libvirt level, but cgroups is limited as it does not support
  some storage devices (such as image files over NFS) and throttles the whole
  virtual machine, including access to meta-data, while qemu I/O is more
  fine-grained. (BZ#956825)
  
• Patches were added to the QEMU block driver for accessing CEPH storage on
  qemu-kvm-rhev. However,this is not usable on its own, a librbd library
  still needs to be provided. The librbd library is not provided in Red Hat
  Enterprise Linux and will be handled by a third party source. (BZ#988079)
  

Solution

All Red Hat Enterprise Virtualization users with deployed virtualization
hosts are advised to install these updated packages, which contain
backported patches to correct these issues and add these enhancements.

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

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/site/articles/11258

Affected Products

• Red Hat Virtualization 3 for RHEL 6 x86_64

Fixes

• BZ - 877240 - QMP: improve error message for blockdev-snapshot-sync failure
• BZ - 987725 - Guest should failed to be booted if specifying iops,bps as negative value
• BZ - 987745 - fail to do hotplug with qemu i/o throttling including iops,iops_wr,iops_rd,bps,bps_wr,bps_rd inofs
• BZ - 1001436 - Qemu core dumped when set iops,bps... to a negative value var monitor
• BZ - 1007330 - CVE-2013-4344 qemu: buffer overflow in scsi_target_emulate_report_luns
• BZ - 1010930 - Qemu-kvm-rhev build verifytest failed (rpm -V)

CVEs

• CVE-2013-4344

References

• https://access.redhat.com/security/updates/classification/#important

Red Hat Virtualization 3 for RHEL 6

SRPM
qemu-kvm-rhev-0.12.1.2-2.415.el6.src.rpm	SHA-256: 1efc57b472ad0aebbd38712d30f50904016e1b557cc4aa72af7aaf5cfdc994fa
x86_64
qemu-img-rhev-0.12.1.2-2.415.el6.x86_64.rpm	SHA-256: b64790eb50d3a351b0bc3d5db065fafff213f101ef0c6e5c3102a985e1175826
qemu-kvm-rhev-0.12.1.2-2.415.el6.x86_64.rpm	SHA-256: 0bad7c66bdd75a19d876a1ec9d7e48b45e9a6520142208fd13825a18486ee6f5
qemu-kvm-rhev-debuginfo-0.12.1.2-2.415.el6.x86_64.rpm	SHA-256: a6abcad8e640c555ab3f5579d52f0aa7ddfea7fc86ae93c942cc3f774a453d66
qemu-kvm-rhev-tools-0.12.1.2-2.415.el6.x86_64.rpm	SHA-256: d8d88f13cdf841154335883e153ae71a943f7dc4e69a39a138f46d4943c5304a