From fa58a9fa74979f845fc6c94a58501e67f3abb6de Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 18 Jul 2018 19:45:51 +0200 Subject: [PATCH] KVM: nVMX: include shadow vmcs12 in nested state The shadow vmcs12 cannot be flushed on KVM_GET_NESTED_STATE, because at that point guest memory is assumed by userspace to be immutable. Capture the cache in vmx_get_nested_state, adding another page at the end if there is an active shadow vmcs12. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 2a005f519032..c7d08a54ab8d 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -13191,9 +13191,15 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, kvm_state.vmx.vmxon_pa = vmx->nested.vmxon_ptr; kvm_state.vmx.vmcs_pa = vmx->nested.current_vmptr; - if (vmx->nested.current_vmptr != -1ull) + if (vmx->nested.current_vmptr != -1ull) { kvm_state.size += VMCS12_SIZE; + if (is_guest_mode(vcpu) && + nested_cpu_has_shadow_vmcs(vmcs12) && + vmcs12->vmcs_link_pointer != -1ull) + kvm_state.size += VMCS12_SIZE; + } + if (vmx->nested.smm.vmxon) kvm_state.vmx.smm.flags |= KVM_STATE_NESTED_SMM_VMXON; @@ -13232,6 +13238,13 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, if (copy_to_user(user_kvm_nested_state->data, vmcs12, sizeof(*vmcs12))) return -EFAULT; + if (nested_cpu_has_shadow_vmcs(vmcs12) && + vmcs12->vmcs_link_pointer != -1ull) { + if (copy_to_user(user_kvm_nested_state->data + VMCS12_SIZE, + get_shadow_vmcs12(vcpu), sizeof(*vmcs12))) + return -EFAULT; + } + out: return kvm_state.size; } @@ -13316,6 +13329,22 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, vmx->nested.nested_run_pending = !!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING); + 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) + 2 * sizeof(*vmcs12)) + return -EINVAL; + + if (copy_from_user(shadow_vmcs12, + user_kvm_nested_state->data + VMCS12_SIZE, + sizeof(*vmcs12))) + return -EFAULT; + + if (shadow_vmcs12->hdr.revision_id != VMCS12_REVISION || + !shadow_vmcs12->hdr.shadow_vmcs) + return -EINVAL; + } + if (check_vmentry_prereqs(vcpu, vmcs12) || check_vmentry_postreqs(vcpu, vmcs12, &exit_qual)) return -EINVAL; -- GitLab