Xenstore, to have an up-to-date picture of the entire system, wants to know of domains appearing and disappearing. To make this more robust, a new XEN_DOMCTL_get_domain_state was introduced. The management of the bitmap underlying that operation is tied into the binding of the VIRQ_DOM_EXC virtual IRQ. Unfortunately an error path there would tear down the bitmap even in cases when it wasn't set up. Unprivileged domains can trigger that error path.

Xenstore, to have an up-to-date picture of the entire system, wants to know of domains appearing and disappearing. To make this more robust, a new XEN_DOMCTL_get_domain_state was introduced. The management of the bitmap underlying that operation is tied into the binding of the VIRQ_DOM_EXC virtual IRQ. Unfortunately an error path there would tear down the bitmap even in cases when it wasn't set up. Unprivileged domains can trigger that error path.

xen-4.22.0_02-1.1 on GA media

Affected: Ubuntu:16.04:LTS: xen, Ubuntu:18.04:LTS: xen, Ubuntu:20.04:LTS: xen, Ubuntu:22.04:LTS: xen, Ubuntu:24.04:LTS: xen, Ubuntu:26.04:LTS: xen

Xenstore, to have an up-to-date picture of the entire system, wants to know of domains appearing and disappearing. To make this more robust, a new XEN_DOMCTL_get_domain_state was introduced. The management of the bitmap underlying that operation is tied into the binding of the VIRQ_DOM_EXC virtual IRQ. Unfortunately an error path there would tear down the bitmap even in cases when it wasn't set up. Unprivileged domains can trigger that error path.

Ein Angreifer kann mehrere Schwachstellen in Xen ausnutzen, um seine Privilegien zu erhöhen, vertrauliche Informationen offenzulegen oder einen Denial-of-Service-Zustand auszulösen.