diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index e762222476a9..f8ad42bcfc2d 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -11755,6 +11755,33 @@ static int check_vmentry_prereqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) return 0; } +static int nested_vmx_check_vmcs_link_ptr(struct kvm_vcpu *vcpu, + struct vmcs12 *vmcs12) +{ + int r; + struct page *page; + struct vmcs12 *shadow; + + if (vmcs12->vmcs_link_pointer == -1ull) + return 0; + + if (!page_address_valid(vcpu, vmcs12->vmcs_link_pointer)) + return -EINVAL; + + page = kvm_vcpu_gpa_to_page(vcpu, vmcs12->vmcs_link_pointer); + if (is_error_page(page)) + return -EINVAL; + + r = 0; + shadow = kmap(page); + if (shadow->hdr.revision_id != VMCS12_REVISION || + shadow->hdr.shadow_vmcs != nested_cpu_has_shadow_vmcs(vmcs12)) + r = -EINVAL; + kunmap(page); + kvm_release_page_clean(page); + return r; +} + static int check_vmentry_postreqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, u32 *exit_qual) { @@ -11766,8 +11793,7 @@ static int check_vmentry_postreqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, !nested_guest_cr4_valid(vcpu, vmcs12->guest_cr4)) return 1; - if (!nested_cpu_has_shadow_vmcs(vmcs12) && - vmcs12->vmcs_link_pointer != -1ull) { + if (nested_vmx_check_vmcs_link_ptr(vcpu, vmcs12)) { *exit_qual = ENTRY_FAIL_VMCS_LINK_PTR; return 1; }