kvm-x86-fix-kvm_apic_has_events-to-check-for-NULL-po.patch


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From: Paolo Bonzini <pbonzini@redhat.com>
Date: Thu, 4 Jun 2015 10:18:22 +0200
Subject: [PATCH] kvm: x86: fix kvm_apic_has_events to check for NULL pointer

Malicious (or egregiously buggy) userspace can trigger it, but it
should never happen in normal operation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/lapic.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 9d28383fc1e7..c4ea87eedf8a 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -150,7 +150,7 @@ static inline bool kvm_apic_vid_enabled(struct kvm *kvm)
 
 static inline bool kvm_apic_has_events(struct kvm_vcpu *vcpu)
 {
-	return vcpu->arch.apic->pending_events;
+	return kvm_vcpu_has_lapic(vcpu) && vcpu->arch.apic->pending_events;
 }
 
 bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);