kvm: nVMX: Set VM instruction error for VMPTRLD of unbacked page (fca91f6d) · Commits · 戴 / test

It is never correct for a VMX instruction to fail with "invalid VMCS" if there is, in fact, a current VMCS. Reads from unbacked addresses return all 1's, which means that an unbacked VMCS will not have the correct VMCS revision ID (i.e. VMCS12_REVISION). Fixes: ("KVM: nVMX: Implement VMPTRLD") Signed-off-by:

Jim Mattson <jmattson@google.com> Signed-off-by:

Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx.c

+11 −3

Original line number	Diff line number	Diff line
		@@ -9318,9 +9318,17 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu)
		struct vmcs12 *new_vmcs12;
		struct page *page;
		page = kvm_vcpu_gpa_to_page(vcpu, vmptr);
		if (is_error_page(page))
		return nested_vmx_failInvalid(vcpu);

		if (is_error_page(page)) {
		/*
		* Reads from an unbacked page return all 1s,
		* which means that the 32 bits located at the
		* given physical address won't match the required
		* VMCS12_REVISION identifier.
		*/
		nested_vmx_failValid(vcpu,
		VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID);
		return kvm_skip_emulated_instruction(vcpu);
		}
		new_vmcs12 = kmap(page);
		if (new_vmcs12->hdr.revision_id != VMCS12_REVISION \|\|
		(new_vmcs12->hdr.shadow_vmcs &&

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