KVM: nVMX: fix vmentry failure code when L2 state would require emulation
Commit 2bb8cafea80b ("KVM: vVMX: signal failure for nested VMEntry if
emulation_required", 2018-03-12) introduces a new error path which does
not set *entry_failure_code. Fix that to avoid a leak of L0 stack to L1.
Reported-by: Radim Krčmář <rkrcmar@redhat.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 1b8d122..1eb06f7 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -11059,8 +11059,10 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
* which means L1 attempted VMEntry to L2 with invalid state.
* Fail the VMEntry.
*/
- if (vmx->emulation_required)
+ if (vmx->emulation_required) {
+ *entry_failure_code = ENTRY_FAIL_DEFAULT;
return 1;
+ }
/* Shadow page tables on either EPT or shadow page tables. */
if (nested_vmx_load_cr3(vcpu, vmcs12->guest_cr3, nested_cpu_has_ept(vmcs12),