tree f1de2ce3a27fe310faea6a252a88bce39946383c
parent 7cbb39d4d4d530dff12f2ff06ed6c85c504ba91a
author Paolo Bonzini <pbonzini@redhat.com> 1396035710 +0100
committer Paolo Bonzini <pbonzini@redhat.com> 1396624634 +0200

KVM: ioapic: fix assignment of ioapic->rtc_status.pending_eoi (CVE-2014-0155)

QE reported that they got the BUG_ON in ioapic_service to trigger.
I cannot reproduce it, but there are two reasons why this could happen.

The less likely but also easiest one, is when kvm_irq_delivery_to_apic
does not deliver to any APIC and returns -1.

Because irqe.shorthand == 0, the kvm_for_each_vcpu loop in that
function is never reached.  However, you can target the similar loop in
kvm_irq_delivery_to_apic_fast; just program a zero logical destination
address into the IOAPIC, or an out-of-range physical destination address.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>