Commit 8cdba919 authored Aug 10, 2022 by Vitaly Kuznetsov Committed by Greg Kroah-Hartman Aug 25, 2022

KVM: x86: Avoid theoretical NULL pointer dereference in kvm_irq_delivery_to_apic_fast()



commit 00b5f37189d24ac3ed46cb7f11742094778c46ce upstream

When kvm_irq_delivery_to_apic_fast() is called with APIC_DEST_SELF
shorthand, 'src' must not be NULL. Crash the VM with KVM_BUG_ON()
instead of crashing the host.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20220325132140.25650-3-vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Ghinea <stefan.ghinea@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 8fb5e776

arch/x86/kvm/lapic.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -955,6 +955,10 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm kvm, struct kvm_lapic src,
		*r = -1;

		if (irq->shorthand == APIC_DEST_SELF) {
		if (KVM_BUG_ON(!src, kvm)) {
		*r = 0;
		return true;
		}
		*r = kvm_apic_set_irq(src->vcpu, irq, dest_map);
		return true;
		}