kvm: nVMX: Validate the virtual-APIC address on nested VM-entry

According to the SDM, if the "use TPR shadow" VM-execution control is
1, bits 11:0 of the virtual-APIC address must be 0 and the address
should set any bits beyond the processor's physical-address width.

Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e0d2ca0927882b2f7e7d3e587a18d6166ee1e642..ec6b1932dea9f08b1dd2bf45240f36ddfc62eec1 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -9993,6 +9993,18 @@ static int nested_vmx_check_msr_bitmap_controls(struct kvm_vcpu *vcpu,
        return 0;
 }
 
+static int nested_vmx_check_tpr_shadow_controls(struct kvm_vcpu *vcpu,
+                                               struct vmcs12 *vmcs12)
+{
+       if (!nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW))
+               return 0;
+
+       if (!page_address_valid(vcpu, vmcs12->virtual_apic_page_addr))
+               return -EINVAL;
+
+       return 0;
+}
+
 /*
  * Merge L0's and L1's MSR bitmap, return false to indicate that
  * we do not use the hardware.
@@ -10680,6 +10692,9 @@ static int check_vmentry_prereqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
        if (nested_vmx_check_msr_bitmap_controls(vcpu, vmcs12))
                return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
 
+       if (nested_vmx_check_tpr_shadow_controls(vcpu, vmcs12))
+               return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+
        if (nested_vmx_check_apicv_controls(vcpu, vmcs12))
                return VMXERR_ENTRY_INVALID_CONTROL_FIELD;