The physdev_get_free_pirq hypercall in arch/x86/physdev.c in Xen 4.1.x and Citrix...

Vulnerability Description

The physdev_get_free_pirq hypercall in arch/x86/physdev.c in Xen 4.1.x and Citrix XenServer 6.0.2 and earlier uses the return value of the get_free_pirq function as an array index without checking that the return value indicates an error, which allows guest OS users to cause a denial of service (invalid memory write and host crash) and possibly gain privileges via unspecified vectors.

References

• http://secunia.com/advisories/55082
• http://xenbits.xen.org/hg/xen-4.1-testing.hg/rev/6779ddca8593
• http://lists.xen.org/archives/html/xen-announce/2012-09/msg00001.html
• http://secunia.com/advisories/51413
• http://security.gentoo.org/glsa/glsa-201309-24.xml
• http://wiki.xen.org/wiki/Security_Announcements#XSA-13_hypercall_physdev_get_free_pirq_vulnerability
• http://lists.opensuse.org/opensuse-security-announce/2012-11/msg00017.html
• http://www.securityfocus.com/bid/55406
• http://www.securitytracker.com/id?1027480
• https://security.gentoo.org/glsa/201604-03
• http://lists.opensuse.org/opensuse-security-announce/2012-09/msg00003.html
• http://support.citrix.com/article/CTX134708
• http://www.openwall.com/lists/oss-security/2012/09/05/6
• http://lists.opensuse.org/opensuse-security-announce/2012-09/msg00004.html
• http://lists.opensuse.org/opensuse-security-announce/2012-11/msg00018.html
• http://lists.opensuse.org/opensuse-security-announce/2012-09/msg00017.html