[PATCH 1/3] KVM: nSVM: Check addresses of MSR and IO bitmap

[Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>]

According to section "Canonicalization and Consistency Checks" in APM vol 2,
the following guest state is illegal:

    "The MSR or IOIO intercept tables extend to a physical address that
     is greater than or equal to the maximum supported physical address."

Also check that these addresses are aligned on page boundary.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>
---
 arch/x86/kvm/svm/nested.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index cb4c6ee10029..389a8108ddb5 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -211,8 +211,11 @@ static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
 	return true;
 }
 
-static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
+static bool nested_vmcb_check_controls(struct vcpu_svm *svm,
+				       struct vmcb_control_area *control)
 {
+	int maxphyaddr;
+
 	if ((vmcb_is_intercept(control, INTERCEPT_VMRUN)) == 0)
 		return false;
 
@@ -223,6 +226,14 @@ static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
 	    !npt_enabled)
 		return false;
 
+	maxphyaddr = cpuid_maxphyaddr(&svm->vcpu);
+	if (!IS_ALIGNED(control->msrpm_base_pa, PAGE_SIZE) ||
+	    control->msrpm_base_pa >> maxphyaddr)
+		return false;
+	if (!IS_ALIGNED(control->iopm_base_pa, PAGE_SIZE) ||
+	    control->iopm_base_pa >> maxphyaddr)
+		return false;
+
 	return true;
 }
 
@@ -258,7 +269,7 @@ static bool nested_vmcb_checks(struct vcpu_svm *svm, struct vmcb *vmcb12)
 	if (!kvm_is_valid_cr4(&svm->vcpu, vmcb12->save.cr4))
 		return false;
 
-	return nested_vmcb_check_controls(&vmcb12->control);
+	return nested_vmcb_check_controls(svm, &vmcb12->control);
 }
 
 static void load_nested_vmcb_control(struct vcpu_svm *svm,
@@ -1173,7 +1184,7 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
 		goto out_free;
 
 	ret = -EINVAL;
-	if (!nested_vmcb_check_controls(ctl))
+	if (!nested_vmcb_check_controls(svm, ctl))
 		goto out_free;
 
 	/*
-- 
2.27.0