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

xen-tools -- PCI MSI mask bits inadvertently exposed to guests

Affected packages
3.3	<=	xen-tools	<	4.5.0_6

Details

VuXML ID	4db8a0f4-27e9-11e5-a4a5-002590263bf5
Discovery	2015-06-02
Entry	2015-07-11

The Xen Project reports:

The mask bits optionally available in the PCI MSI capability structure are used by the hypervisor to occasionally suppress interrupt delivery. Unprivileged guests were, however, nevertheless allowed direct control of these bits.

Interrupts may be observed by Xen at unexpected times, which may lead to a host crash and therefore a Denial of Service.

[source]

References

CVE Name	CVE-2015-4104
URL	http://xenbits.xen.org/xsa/advisory-129.html