From: Liran Alon <liran.alon@oracle.com>
Date: Fri, 22 Jun 2018 23:35:04 +0000 (+0300)
Subject: KVM: nVMX: Fail VMLAUNCH and VMRESUME on shadow VMCS
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=a6192d40d52f6b86997a71449e2ebc3d7f5ca103;p=openwrt%2Fstaging%2Fblogic.git

KVM: nVMX: Fail VMLAUNCH and VMRESUME on shadow VMCS

Signed-off-by: Liran Alon <liran.alon@oracle.com>
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 44e2b82f6519..f6ec898ac539 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -11876,6 +11876,17 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
 
 	vmcs12 = get_vmcs12(vcpu);
 
+	/*
+	 * Can't VMLAUNCH or VMRESUME a shadow VMCS. Despite the fact
+	 * that there *is* a valid VMCS pointer, RFLAGS.CF is set
+	 * rather than RFLAGS.ZF, and no error number is stored to the
+	 * VM-instruction error field.
+	 */
+	if (vmcs12->hdr.shadow_vmcs) {
+		nested_vmx_failInvalid(vcpu);
+		goto out;
+	}
+
 	if (enable_shadow_vmcs)
 		copy_shadow_to_vmcs12(vmx);