CVE-2010-4255 Information

Description

The fixup_page_fault function in arch/x86/traps.c in Xen 4.0.1 and earlier on 64-bit platforms when paravirtualization is enabled does not verify that kernel mode is used to call the handle_gdt_ldt_mapping_fault function which allows guest OS users to cause a denial of service (host OS BUG_ON) via a crafted memory access.

Reference

http://lists.xensource.com/archives/html/xen-devel/2010-11/msg01650.html http://openwall.com/lists/oss-security/2010/11/30/5 http://openwall.com/lists/oss-security/2010/11/30/8 http://secunia.com/advisories/42884 http://secunia.com/advisories/46397 http://www.redhat.com/support/errata/RHSA-2011-0017.html http://www.securityfocus.com/archive/1/520102/100/0/threaded http://www.vmware.com/security/advisories/VMSA-2011-0012.html https://bugzilla.redhat.com/show_bug.cgi?id=658155