KVM: x86: fix user triggerable warning in kvm_apic_accept_events()
If we already entered/are about to enter SMM, don't allow switching to
INIT/SIPI_RECEIVED, otherwise the next call to kvm_apic_accept_events()
will report a warning.
Same applies if we are already in MP state INIT_RECEIVED and SMM is
requested to be turned on. Refuse to set the VCPU events in this case.
Fixes: cd7764fe9f73 ("KVM: x86: latch INITs while in system management mode")
Cc: stable@vger.kernel.org # 4.2+
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bb3a153..722fe85 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3114,6 +3114,12 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
(events->exception.nr > 31 || events->exception.nr == NMI_VECTOR))
return -EINVAL;
+ /* INITs are latched while in SMM */
+ if (events->flags & KVM_VCPUEVENT_VALID_SMM &&
+ (events->smi.smm || events->smi.pending) &&
+ vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED)
+ return -EINVAL;
+
process_nmi(vcpu);
vcpu->arch.exception.pending = events->exception.injected;
vcpu->arch.exception.nr = events->exception.nr;
@@ -7342,6 +7348,12 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
mp_state->mp_state != KVM_MP_STATE_RUNNABLE)
return -EINVAL;
+ /* INITs are latched while in SMM */
+ if ((is_smm(vcpu) || vcpu->arch.smi_pending) &&
+ (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED ||
+ mp_state->mp_state == KVM_MP_STATE_INIT_RECEIVED))
+ return -EINVAL;
+
if (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED) {
vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
set_bit(KVM_APIC_SIPI, &vcpu->arch.apic->pending_events);