Synopsis

Moderate: libvirt security, bug fix, and enhancement update

Type/Severity

Security Advisory: Moderate

Topic

Updated libvirt packages that fix one security issue, several bugs and add
various enhancements are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate
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

The libvirt library is a C API for managing and interacting with the
virtualization capabilities of Linux and other operating systems.

An integer overflow flaw was found in libvirtd's RPC call handling. An
attacker able to establish read-only connections to libvirtd could trigger
this flaw by calling virDomainGetVcpus() with specially-crafted parameters,
causing libvirtd to crash. (CVE-2011-2511)

This update fixes the following bugs:

• libvirt was rebased from version 0.6.3 to version 0.8.2 in Red Hat
  Enterprise Linux 5.6. A code audit found a minor API change that effected
  error messages seen by libvirt 0.8.2 clients talking to libvirt 0.7.1 -
  0.7.7 (0.7.x) servers. A libvirt 0.7.x server could send
  VIR_ERR_BUILD_FIREWALL errors where a libvirt 0.8.2 client expected
  VIR_ERR_CONFIG_UNSUPPORTED errors. In other circumstances, a libvirt 0.8.2
  client saw a "Timed out during operation" message where it should see an
  "Invalid network filter" error. This update adds a backported patch that
  allows libvirt 0.8.2 clients to interoperate with the API as used by
  libvirt 0.7.x servers, ensuring correct error messages are sent.
  (BZ#665075)
  
• libvirt could crash if the maximum number of open file descriptors
  (_SC_OPEN_MAX) grew larger than the FD_SETSIZE value because it accessed
  file descriptors outside the bounds of the set. With this update the
  maximum number of open file descriptors can no longer grow larger than the
  FD_SETSIZE value. (BZ#665549)
  
• A libvirt race condition was found. An array in the libvirt event
  handlers was accessed with a lock temporarily released. In rare cases, if
  one thread attempted to access this array but a second thread reallocated
  the array before the first thread reacquired a lock, it could lead to the
  first thread attempting to access freed memory, potentially causing libvirt
  to crash. With this update libvirt no longer refers to the old array and,
  consequently, behaves as expected. (BZ#671569)
  
• Guests connected to a passthrough NIC would kernel panic if a
  system_reset signal was sent through the QEMU monitor. With this update you
  can reset such guests as expected. (BZ#689880)
  
• When using the Xen kernel, the rpmbuild command failed on the xencapstest
  test. With this update you can run rpmbuild successfully when using the Xen
  kernel. (BZ#690459)
  
• When a disk was hot unplugged, "ret >= 0" was passed to the qemuAuditDisk
  calls in disk hotunplug operations before ret was, in fact, set to 0. As
  well, the error path jumped to the "cleanup" label prematurely. As a
  consequence, hotunplug failures were not audited and hotunplug successes
  were audited as failures. This was corrected and hot unplugging checks now
  behave as expected. (BZ#710151)
  
• A conflict existed between filter update locking sequences and virtual
  machine startup locking sequences. When a filter update occurred on one or
  more virtual machines, a deadlock could consequently occur if a virtual
  machine referencing a filter was started. This update changes and makes
  more flexible several qemu locking sequences ensuring this deadlock no
  longer occurs. (BZ#697749)
  
• qemudDomainSaveImageStartVM closed some incoming file descriptor (fd)
  arguments without informing the caller. The consequent double-closes could
  cause Domain restoration failure. This update alters the
  qemudDomainSaveImageStartVM signature to prevent the double-closes.
  (BZ#681623)
  

This update also adds the following enhancements:

• The libvirt Xen driver now supports more than one serial port.
  (BZ#670789)
  
• Enabling and disabling the High Precision Event Timer (HPET) in Xen
  domains is now possible. (BZ#703193)
  

All libvirt users should install this update which addresses this
vulnerability, fixes these bugs and adds these enhancements. After
installing the updated packages, libvirtd must be restarted ("service
libvirtd restart") for this update to take effect.

Solution

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/kb/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386

Fixes

• BZ - 665075 - minor libvirt API break in error reporting
• BZ - 665549 - libvirt crash on src/util/util.c in __virExec
• BZ - 671569 - race condition in libvirt could lead to crash on event handling
• BZ - 681623 - libvirt double-close bug in tight loop of save/restore [5.7]
• BZ - 689880 - guest with passthrough nic got kernel panic when send system_reset signal in QEMU monitor
• BZ - 690459 - rpmbuild failed on xencapstest when running under xen kernel
• BZ - 697749 - Deadlock between VM ops and filter update
• BZ - 703193 - support enabling/disabling xen hpet
• BZ - 710151 - Auditing of QEMU driver disk hotunplug events logs is missing and/or incorrect
• BZ - 717199 - CVE-2011-2511 libvirt: integer overflow in VirDomainGetVcpus

CVEs

• CVE-2011-2511

References

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

Red Hat Enterprise Linux Server 5

SRPM
libvirt-0.8.2-22.el5.src.rpm	SHA-256: 1f2397e3739427f8e49671f8bae37979d97ec487a7eb327eafd9f3064cec93c5
x86_64
libvirt-0.8.2-22.el5.i386.rpm	SHA-256: 3d00b1f675f03b637ecb34a0650374cfd1b0fec846359d9d51ce0dfd8d037e65
libvirt-0.8.2-22.el5.x86_64.rpm	SHA-256: 33d024f2b84dc254b6ba67da7b9587266c5015590b06e742eba73caa389cfdfa
libvirt-devel-0.8.2-22.el5.i386.rpm	SHA-256: 780ad83c7f0ef21caeeec0a9b95d839b318a2fcbbd2db9288d2713a69704f009
libvirt-devel-0.8.2-22.el5.x86_64.rpm	SHA-256: 5e271376eab75f5fd85bd4e4f29bc106b5fffda3d37b3c9fe2f15932a60fe9f0
libvirt-python-0.8.2-22.el5.x86_64.rpm	SHA-256: cdb8ffea1812c71c10e69a5890316874febc4593c0dbed632a92de5229cd6ea0
ia64
libvirt-0.8.2-22.el5.ia64.rpm	SHA-256: 8b4a429daf1b9f002879dd356f320ffff1afdfb34c68d1fd1e88ca6aa05362e7
libvirt-devel-0.8.2-22.el5.ia64.rpm	SHA-256: 6a402164c7464afc58e938efa31d1b79fb8638765374f4a1e31adc753ad038e4
libvirt-python-0.8.2-22.el5.ia64.rpm	SHA-256: c9558a20f873f719bd967179d7c28b2ed53060f20550b7d93684d8aae26f1cb7
i386
libvirt-0.8.2-22.el5.i386.rpm	SHA-256: 3d00b1f675f03b637ecb34a0650374cfd1b0fec846359d9d51ce0dfd8d037e65
libvirt-devel-0.8.2-22.el5.i386.rpm	SHA-256: 780ad83c7f0ef21caeeec0a9b95d839b318a2fcbbd2db9288d2713a69704f009
libvirt-python-0.8.2-22.el5.i386.rpm	SHA-256: 123557258c646c6f0ddba454186b34b9699e6f488118108b751240063861a45f

Red Hat Enterprise Linux Workstation 5

SRPM
libvirt-0.8.2-22.el5.src.rpm	SHA-256: 1f2397e3739427f8e49671f8bae37979d97ec487a7eb327eafd9f3064cec93c5
x86_64
libvirt-0.8.2-22.el5.i386.rpm	SHA-256: 3d00b1f675f03b637ecb34a0650374cfd1b0fec846359d9d51ce0dfd8d037e65
libvirt-0.8.2-22.el5.x86_64.rpm	SHA-256: 33d024f2b84dc254b6ba67da7b9587266c5015590b06e742eba73caa389cfdfa
libvirt-devel-0.8.2-22.el5.i386.rpm	SHA-256: 780ad83c7f0ef21caeeec0a9b95d839b318a2fcbbd2db9288d2713a69704f009
libvirt-devel-0.8.2-22.el5.x86_64.rpm	SHA-256: 5e271376eab75f5fd85bd4e4f29bc106b5fffda3d37b3c9fe2f15932a60fe9f0
libvirt-python-0.8.2-22.el5.x86_64.rpm	SHA-256: cdb8ffea1812c71c10e69a5890316874febc4593c0dbed632a92de5229cd6ea0
i386
libvirt-0.8.2-22.el5.i386.rpm	SHA-256: 3d00b1f675f03b637ecb34a0650374cfd1b0fec846359d9d51ce0dfd8d037e65
libvirt-devel-0.8.2-22.el5.i386.rpm	SHA-256: 780ad83c7f0ef21caeeec0a9b95d839b318a2fcbbd2db9288d2713a69704f009
libvirt-python-0.8.2-22.el5.i386.rpm	SHA-256: 123557258c646c6f0ddba454186b34b9699e6f488118108b751240063861a45f