David Gibson

The issue is related to errors in saving and restoring the state of register masks for power save functionality, specifically PNV POWERSAVE AMR, PNV POWERSAVE UAMOR, and PNV POWERSAVE AMOR, in the Linux kernel on the powerpc platform. This could allow an attacker to cause a denial of service.

The issue allows local users to cause a denial of service, resulting in a system crash due to a NULL pointer dereference. This can be achieved by making a KVM CHECK EXTENSION KVM CAP PPC HTM ioctl call to the `/dev/kvm` API endpoint.

The issue allows privileged guest users to cause the host to become unavailable to the management server by sending a guest agent response containing invalid XML characters. This is due to an incomplete fix for a previous issue.