add-to-physmap error paths fail to release lock on ARM

ISSUE DESCRIPTION When dealing with the grant map space of add-to-physmap operations, ARM specific code recognizes a number of error conditions, but fails to release a lock being held on the respective exit paths. IMPACT A malicious guest administrator can cause a denial of service. Specifically,...

Debian DSA-2582-1 : xen - several vulnerabilities

Multiple denial of service vulnerabilities have been discovered in the Xen Hypervisor. One of the issue CVE-2012-5513 could even lead to privilege escalation from guest to host. Some of the recently published Xen Security Advisories XSA 25and 28 are not fixed by this update and should be fixed in...

Broken error handling in guest_physmap_mark_populate_on_demand()

ISSUE DESCRIPTION guestphysmapmarkpopulateondemand, before carrying out its actual operation, checks that the subject GFNs are not in use. If that check fails, the code prints a message and bypasses the gfnunlock matching the gfnlock carried out before entering the loop. Further, the function is...

XENMEM_populate_physmap DoS vulnerability

ISSUE DESCRIPTION XENMEMpopulatephysmap can be called with invalid flags. By calling it with MEMFpopulateondemand flag set, a BUG can be triggered if a translating paging mode is not being used. IMPACT A malicious guest kernel can crash the host. VULNERABLE SYSTEMS All Xen systems running PV...