FreeBSD VuXML: Documenting security issues in FreeBSD and the FreeBSD Ports Collection

xen-kernel -- Long latency populate-on-demand operation is not preemptible

Affected packages
3.4 <= xen-kernel < 4.5.1_1

Details

VuXML ID 83350009-881e-11e5-ab94-002590263bf5
Discovery 2015-10-29
Entry 2015-11-11

The Xen Project reports:

When running an HVM domain in Populate-on-Demand mode, Xen would sometimes search the domain for memory to reclaim, in response to demands for population of other pages in the same domain. This search runs without preemption. The guest can, by suitable arrangement of its memory contents, create a situation where this search is a time-consuming linear scan of the guest's address space.

A malicious HVM guest administrator can cause a denial of service. Specifically, prevent use of a physical CPU for a significant period.

References

CVE Name CVE-2015-7970
URL http://xenbits.xen.org/xsa/advisory-150.html