7.8 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:N/I:N/A:C
0.002 Low
EPSS
Percentile
60.9%
KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems. KVM is a Linux kernel module built for
the standard Red Hat Enterprise Linux kernel.
On x86 platforms, the do_insn_fetch() function did not limit the amount of
instruction bytes fetched per instruction. Users in guest operating systems
could leverage this flaw to cause large latencies on SMP hosts that could
lead to a local denial of service on the host operating system. This
update fixes this issue by imposing the architecturally-defined 15 byte
length limit for instructions. (CVE-2009-4031)
This update also fixes the following bugs:
performance problems occurred when using the qcow2 image format with the
qemu-kvm -drive βcache=noneβ option (the default setting when not specified
otherwise). This could cause guest operating system installations to take
hours. With this update, performance patches have been backported so that
using the qcow2 image format with the βcache=noneβ option no longer causes
performance issues. (BZ#520693)
when using the virtual vm8086 mode, bugs in the emulated hardware task
switching implementation may have, in some situations, caused older guest
operating systems to malfunction. (BZ#532031)
Windows Server 2003 guests (32-bit) with more than 4GB of memory may have
crashed during reboot when using the default qemu-kvm CPU settings.
(BZ#532043)
with Red Hat Enterprise Virtualization, guests continued to run after
encountering disk read errors. This could have led to their file systems
becoming corrupted (but not the hostβs), notably in environments that use
networked storage. With this update, the qemu-kvm -drive βwerror=stopβ
option now applies not only to write errors but also to read errors: When
using this option, guests will pause on disk read and write errors.
By default, guests managed by Red Hat Enterprise Virtualization use the
βwerror=stopβ option. This option is not used by default for guests managed
by libvirt. (BZ#537334, BZ#540406)
All KVM users should upgrade to these updated packages, which contain
backported patches to resolve these issues. Note: The procedure in the
Solution section must be performed before this update will take effect.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
RedHat | 5 | x86_64 | kvm-tools | <Β 83-105.el5_4.13 | kvm-tools-83-105.el5_4.13.x86_64.rpm |
RedHat | 5 | x86_64 | kmod-kvm | <Β 83-105.el5_4.13 | kmod-kvm-83-105.el5_4.13.x86_64.rpm |
RedHat | 5 | x86_64 | kvm | <Β 83-105.el5_4.13 | kvm-83-105.el5_4.13.x86_64.rpm |
RedHat | 5 | x86_64 | kvm-qemu-img | <Β 83-105.el5_4.13 | kvm-qemu-img-83-105.el5_4.13.x86_64.rpm |
RedHat | 5 | src | kvm | <Β 83-105.el5_4.13 | kvm-83-105.el5_4.13.src.rpm |