SUSE-SU-2018:1386-1: important: Security update for qemu
sle-updates at lists.suse.com
sle-updates at lists.suse.com
Wed May 23 10:07:22 MDT 2018
SUSE Security Update: Security update for qemu
Announcement ID: SUSE-SU-2018:1386-1
References: #1068032 #1082276 #1092885
Cross-References: CVE-2017-5715 CVE-2018-3639
SUSE Linux Enterprise Server 12-LTSS
An update that solves two vulnerabilities and has one
errata is now available.
This update for qemu fixes several issues.
This security issue was fixed:
- CVE-2018-3639: Spectre v4 vulnerability mitigation support for KVM
Systems with microprocessors utilizing speculative execution and
speculative execution of memory reads before the addresses of all prior
memory writes are known may allow unauthorized disclosure of information
to an attacker with local user access via a side-channel analysis.
This patch permits the new x86 cpu feature flag named "ssbd" to be
presented to the guest, given that the host has this feature, and KVM
exposes it to the guest as well.
For this feature to be enabled please use the qemu commandline
-cpu $MODEL,+spec-ctrl,+ssbd so the guest OS can take advantage of the
spec-ctrl and ssbd support is also required in the host.
- CVE-2017-5715: This update has the next round of Spectre v2 related
patches, which now integrates with corresponding changes in libvirt. A
January 2018 release of qemu initially addressed the Spectre v2
vulnerability for KVM guests by exposing the spec-ctrl feature for all
x86 vcpu types. We remove that initial patch and now rely on patches
from upstream (bsc#1068032).
This update defines spec_ctrl and ibpb cpu feature flags as well as new
cpu models which are clones of existing models with either -IBRS or -IBPB
added to the end of the model name. These new vcpu models explicitly
include the new feature(s), whereas the feature flags can be added to the
cpu parameter as with
other features. In short, for continued Spectre v2 protection, ensure
that either the appropriate cpu feature flag is added to the QEMU
one of the new cpu models is used. Although migration from older
versions is supported, the new cpu features won't be properly exposed
to the guest until it is restarted with the cpu features explicitly
added. A reboot is insufficient.
- A patch is added to continue to detect Spectre v2 mitigation features
(as shown by cpuid), and if found provide that feature to guests, even
on older KVM (kernel) versions which do not yet expose that feature to
To install this SUSE Security Update use the SUSE recommended installation methods
like YaST online_update or "zypper patch".
Alternatively you can run the command listed for your product:
- SUSE Linux Enterprise Server 12-LTSS:
zypper in -t patch SUSE-SLE-SERVER-12-2018-968=1
- SUSE Linux Enterprise Server 12-LTSS (ppc64le s390x x86_64):
- SUSE Linux Enterprise Server 12-LTSS (s390x x86_64):
- SUSE Linux Enterprise Server 12-LTSS (ppc64le):
- SUSE Linux Enterprise Server 12-LTSS (x86_64):
- SUSE Linux Enterprise Server 12-LTSS (noarch):
- SUSE Linux Enterprise Server 12-LTSS (s390x):
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