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4.55. kvm

Updated kvm packages that fix one security issue are now available for Red Hat Enterprise Linux 5.
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 associated with the description below.
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.

Security Fix

CVE-2012-6075
A flaw was found in the way QEMU-KVM emulated the e1000 network interface card when the host was configured to accept jumbo network frames, and a guest using the e1000 emulated driver was not. A remote attacker could use this flaw to crash the guest or, potentially, execute arbitrary code with root privileges in the guest.
All users of kvm are advised to upgrade to these updated packages, which contain backported patches to correct this issue. Note that the procedure in the Solution section must be performed before this update will take effect.
Updated kvm packages that fix three security issues are now available for Red Hat Enterprise Linux 5.
The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links associated with each description below.
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.

Security Fixes

CVE-2013-1796
A flaw was found in the way KVM handled guest time updates when the buffer the guest registered by writing to the MSR_KVM_SYSTEM_TIME machine state register (MSR) crossed a page boundary. A privileged guest user could use this flaw to crash the host or, potentially, escalate their privileges, allowing them to execute arbitrary code at the host kernel level.
CVE-2013-1797
A potential use-after-free flaw was found in the way KVM handled guest time updates when the GPA (guest physical address) the guest registered by writing to the MSR_KVM_SYSTEM_TIME machine state register (MSR) fell into a movable or removable memory region of the hosting user-space process (by default, QEMU-KVM) on the host. If that memory region is deregistered from KVM using KVM_SET_USER_MEMORY_REGION and the allocated virtual memory reused, a privileged guest user could potentially use this flaw to escalate their privileges on the host.
CVE-2013-1798
A flaw was found in the way KVM emulated IOAPIC (I/O Advanced Programmable Interrupt Controller). A missing validation check in the ioapic_read_indirect() function could allow a privileged guest user to crash the host, or read a substantial portion of host kernel memory.
Red Hat would like to thank Andrew Honig of Google for reporting all of these issues.
All users of kvm are advised to upgrade to these updated packages, which contain backported patches to correct these issues. Note that the procedure in the Solution section must be performed before this update will take effect.
Updated kvm packages that fix various bugs are now available for Red Hat Enterprise Linux 5.
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.

Bug Fix

BZ#958359
Previously, tb_invalidate_phys_page_range() incurred a segmentation fault because it walked through an invalid chain of translation blocks. Thus, page_find() returned an incorrect pointer, which was subsequently used by tb_invalidate_phys_page_range() to find the head of the translation block chain. This update corrects the chain of translation blocks and crashes no longer occur.
Users of KVM are advised to upgrade to these updated packages, which fix these bugs. Note that the procedure in the Solution section must be performed before this update will take effect.