From 21be4ca1ea685ab3ccc2fd18babb89bc477a9e5c Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 8 May 2019 11:04:32 -0700 Subject: [PATCH] KVM: nVMX: Clear nested_run_pending if setting nested state fails VMX's nested_run_pending flag is subtly consumed when stuffing state to enter guest mode, i.e. needs to be set according before KVM knows if setting guest state is successful. If setting guest state fails, clear the flag as a nested run is obviously not pending. Reported-by: Aaron Lewis Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/nested.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 2fd251ded754..6b450839c766 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -5423,39 +5423,44 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) return 0; + vmx->nested.nested_run_pending = + !!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING); + + ret = -EINVAL; if (nested_cpu_has_shadow_vmcs(vmcs12) && vmcs12->vmcs_link_pointer != -1ull) { struct vmcs12 *shadow_vmcs12 = get_shadow_vmcs12(vcpu); if (kvm_state->size < sizeof(*kvm_state) + VMCS12_SIZE + sizeof(*vmcs12)) - return -EINVAL; + goto error_guest_mode; if (copy_from_user(shadow_vmcs12, user_kvm_nested_state->data + VMCS12_SIZE, - sizeof(*vmcs12))) - return -EFAULT; + sizeof(*vmcs12))) { + ret = -EFAULT; + goto error_guest_mode; + } if (shadow_vmcs12->hdr.revision_id != VMCS12_REVISION || !shadow_vmcs12->hdr.shadow_vmcs) - return -EINVAL; + goto error_guest_mode; } if (nested_vmx_check_controls(vcpu, vmcs12) || nested_vmx_check_host_state(vcpu, vmcs12) || nested_vmx_check_guest_state(vcpu, vmcs12, &exit_qual)) - return -EINVAL; + goto error_guest_mode; vmx->nested.dirty_vmcs12 = true; - vmx->nested.nested_run_pending = - !!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING); - ret = nested_vmx_enter_non_root_mode(vcpu, false); - if (ret) { - vmx->nested.nested_run_pending = 0; - return -EINVAL; - } + if (ret) + goto error_guest_mode; return 0; + +error_guest_mode: + vmx->nested.nested_run_pending = 0; + return ret; } void nested_vmx_vcpu_setup(void)