[PATCH 1/2 v4] KVM: nSVM: Check reserved values for 'Type' and invalid vectors in EVENTINJ

[Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>]

According to sections "Canonicalization and Consistency Checks" and "Event
Injection" in APM vol 2

    VMRUN exits with VMEXIT_INVALID error code if either:
      - Reserved values of TYPE have been specified, or
      - TYPE = 3 (exception) has been specified with a vector that does not
	correspond to an exception (this includes vector 2, which is an NMI,
	not an exception).

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>
---
 arch/x86/include/asm/svm.h |  4 ++++
 arch/x86/kvm/svm/nested.c  | 14 ++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 71d630bb5e08..d676f140cd19 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -341,9 +341,13 @@ struct vmcb {
 #define SVM_EVTINJ_TYPE_MASK (7 << SVM_EVTINJ_TYPE_SHIFT)
 
 #define SVM_EVTINJ_TYPE_INTR (0 << SVM_EVTINJ_TYPE_SHIFT)
+#define SVM_EVTINJ_TYPE_RESV1 (1 << SVM_EVTINJ_TYPE_SHIFT)
 #define SVM_EVTINJ_TYPE_NMI (2 << SVM_EVTINJ_TYPE_SHIFT)
 #define SVM_EVTINJ_TYPE_EXEPT (3 << SVM_EVTINJ_TYPE_SHIFT)
 #define SVM_EVTINJ_TYPE_SOFT (4 << SVM_EVTINJ_TYPE_SHIFT)
+#define SVM_EVTINJ_TYPE_RESV5 (5 << SVM_EVTINJ_TYPE_SHIFT)
+#define SVM_EVTINJ_TYPE_RESV6 (6 << SVM_EVTINJ_TYPE_SHIFT)
+#define SVM_EVTINJ_TYPE_RESV7 (7 << SVM_EVTINJ_TYPE_SHIFT)
 
 #define SVM_EVTINJ_VALID (1 << 31)
 #define SVM_EVTINJ_VALID_ERR (1 << 11)
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 9e4c226dbf7d..fa51231c1f24 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -212,6 +212,9 @@ static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
 
 static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
 {
+	u8 type, vector;
+	bool valid;
+
 	if ((vmcb_is_intercept(control, INTERCEPT_VMRUN)) == 0)
 		return false;
 
@@ -222,6 +225,17 @@ static bool nested_vmcb_check_controls(struct vmcb_control_area *control)
 	    !npt_enabled)
 		return false;
 
+	valid = control->event_inj & SVM_EVTINJ_VALID;
+	type = control->event_inj & SVM_EVTINJ_TYPE_MASK;
+	if (valid && (type == SVM_EVTINJ_TYPE_RESV1 ||
+	    type >= SVM_EVTINJ_TYPE_RESV5))
+		return false;
+
+	vector = control->event_inj & SVM_EVTINJ_VEC_MASK;
+	if (valid && (type == SVM_EVTINJ_TYPE_EXEPT))
+		if (vector == NMI_VECTOR || vector > 31)
+			return false;
+
 	return true;
 }
 
-- 
2.27.0