Synopsis

Important: qemu-kvm-rhev security and bug fix update

Type/Severity

Security Advisory: Important

Topic

An update for qemu-kvm-rhev is now available for Red Hat Virtualization 4 for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

KVM (Kernel-based Virtual Machine) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm-rhev packages provide the user-space component for running virtual machines that use KVM in environments managed by Red Hat products.

Security Fix(es):

• An industry-wide issue was found in the way many modern microprocessor designs have implemented speculative execution of Load & Store instructions (a commonly used performance optimization). It relies on the presence of a precisely-defined instruction sequence in the privileged code as well as the fact that memory read from address to which a recent memory write has occurred may see an older value and subsequently cause an update into the microprocessor's data cache even for speculatively executed instructions that never actually commit (retire). As a result, an unprivileged attacker could use this flaw to read privileged memory by conducting targeted cache side-channel attacks. (CVE-2018-3639)
  

Red Hat would like to thank Ken Johnson (Microsoft Security Response Center) and Jann Horn (Google Project Zero) for reporting this issue.

Note: This is the qemu-kvm-rhev side of the CVE-2018-3639 mitigation that includes support for guests running on hosts with AMD processors.

Bug Fix(es):

• Previously, using device passthrough for a SCSI-2 device failed and returned an "Illegal Request" error. With this update, the QEMU emulator checks the SCSI version of the device when performing passthrough. As a result, the described problem no longer occurs. (BZ#1571370)
  
• Under certain circumstances, resuming a paused guest generated redundant "VIR_DOMAIN_PAUSED_UNKNOWN" error messages in the libvirt log. This update corrects the event sending order when resuming guests, which prevents the errors being logged. (BZ#1582122)
  

Enhancement(s):

• With this update, Ceph storage is supported by KVM virtualization on all CPU architectures supported by Red Hat. (BZ#1588001)

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

After installing this update, shut down all running virtual machines. Once all virtual machines have shut down, start them again for this update to take effect.

Affected Products

• Red Hat Virtualization 4 for RHEL 7 x86_64
• Red Hat Virtualization for IBM Power LE 4 for RHEL 7 ppc64le

Fixes

• BZ - 1566890 - CVE-2018-3639 hw: cpu: speculative store bypass
• BZ - 1582122 - IOERROR pause code lost after resuming a VM while I/O error is still present [rhel-7.5.z]
• BZ - 1588001 - Enable Native Ceph support on non x86_64 CPUs [rhel-7.5.z]

CVEs

• CVE-2018-3639

References

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

Red Hat Virtualization 4 for RHEL 7

SRPM
qemu-kvm-rhev-2.10.0-21.el7_5.4.src.rpm	SHA-256: 7394d38b5b5aa84f5dcffa84bd86469b4eb3f0f9bb5ef314f55fb9b93aa86ee5
x86_64
qemu-img-rhev-2.10.0-21.el7_5.4.x86_64.rpm	SHA-256: 3df36afa855d605fca0ed063cb17c5821f247c1c788a4f26b7cb705d5dd8df00
qemu-kvm-common-rhev-2.10.0-21.el7_5.4.x86_64.rpm	SHA-256: fec123aa073956b5c595d1734070d0871e73863d3ca7b5f9a59eabf85d577591
qemu-kvm-rhev-2.10.0-21.el7_5.4.x86_64.rpm	SHA-256: 809abace96388d691dd8ed04c8a0936f1bacc1e473681913850579d0ac73f587
qemu-kvm-rhev-debuginfo-2.10.0-21.el7_5.4.x86_64.rpm	SHA-256: 802259f15e52c3ce24688d9bc92011365a6077c8521d09264c161ee21be8c9c7
qemu-kvm-tools-rhev-2.10.0-21.el7_5.4.x86_64.rpm	SHA-256: bf930460411fcee2d4298d4f4e2efa23826391a652722a2115a80526175e25ba

Red Hat Virtualization for IBM Power LE 4 for RHEL 7

SRPM
qemu-kvm-rhev-2.10.0-21.el7_5.4.src.rpm	SHA-256: 7394d38b5b5aa84f5dcffa84bd86469b4eb3f0f9bb5ef314f55fb9b93aa86ee5
ppc64le
qemu-img-rhev-2.10.0-21.el7_5.4.ppc64le.rpm	SHA-256: ce39d9f67149d151f69982861d47b47fa9ecb1fd0108e26839fac9f7bf00ab1f
qemu-kvm-common-rhev-2.10.0-21.el7_5.4.ppc64le.rpm	SHA-256: 1886e7879ee1085bf58335e862cff341a6b59a79a457a1ae88bd965f676a7844
qemu-kvm-rhev-2.10.0-21.el7_5.4.ppc64le.rpm	SHA-256: 516a0ef1e60b48c39186fff829a725031c8e54e08eed182aadf0d83cbc2cb570
qemu-kvm-rhev-debuginfo-2.10.0-21.el7_5.4.ppc64le.rpm	SHA-256: e349331a9630b40872721181f7e4e25006e87fa64d81a40a5ee2c15102628295
qemu-kvm-tools-rhev-2.10.0-21.el7_5.4.ppc64le.rpm	SHA-256: ad985ee16015d290e90254b7e6562250ec73e4b99ca6d2a35921993e25575335