From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0144BC54FD0 for ; Mon, 23 Mar 2020 14:51:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CA66A20786 for ; Mon, 23 Mar 2020 14:51:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="DtWQ1WCh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727046AbgCWOvZ (ORCPT ); Mon, 23 Mar 2020 10:51:25 -0400 Received: from us-smtp-delivery-74.mimecast.com ([216.205.24.74]:30750 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727011AbgCWOvZ (ORCPT ); Mon, 23 Mar 2020 10:51:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1584975084; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=5hQzIwtp3bgtyhedyuAt37bjmJHfQ80rOAEIpq2q59s=; b=DtWQ1WChViEzBXmBkyO11LN9ssTwCcNkb8H7GtTFkpeuleFgKCkzB7ly0jZv/SiNdrzrJ9 GJEj5cX3TxqtjYFhBiDKdr5BV7wl3h+Et/OLG0k60ofWRAt7YQYjv7XoHdyN6s4OUDilqb 7Djn2Z2rhl2wZWZ7EDy7DElDUSHvgwQ= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-291--_NsWapKPS2Q-94MfDhtXQ-1; Mon, 23 Mar 2020 10:51:23 -0400 X-MC-Unique: -_NsWapKPS2Q-94MfDhtXQ-1 Received: by mail-wr1-f70.google.com with SMTP id y1so2491590wrn.10 for ; Mon, 23 Mar 2020 07:51:22 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=5hQzIwtp3bgtyhedyuAt37bjmJHfQ80rOAEIpq2q59s=; b=fNpRKqa+JS8UL/KedBUgfL2xDZTiKntUWL0dCmKLP/LpYmHHgq0fwqPKqKJQ3V8OXT dG8f22N2kJWbwt9TvSsAYfd+zNsqN28SZIDO0xBZAvxpMv8DIblt0H1/wlcpnWiXV+oa GmJDrNsNFiUvanUEQeFaIA6nr9XdAPUaDKek6JlnXwKHfx3QI1jAhNn68rj7wcFdkYje Tu2g1Eu4NXdw4k6hwjQjccXOvi+FGn5Xh+1yAMJGOo/3FwGas2ZelsjI+ZDrDcE1rRT3 mXwLxdYCglHq/cXZFkHN8D1SeaQ53YKEz83ByYCG21HK9iO64dP5ojbmjSmsOgFCdY75 kdCw== X-Gm-Message-State: ANhLgQ1JWABTD3RoNoFfVQPT59SJ4LERKL6/3EfGh0tUYFOtQB4c1mfE YmdWCXloHzyu1loYFjXvoFIhQlLshx3J5B8w+iWVqEwsFwZxjlRz1WxGs4Xlw4pYeSxcApy7izJ +sRHB6/Gsw7pnhiDwJR4DlUO2 X-Received: by 2002:adf:97c1:: with SMTP id t1mr30336567wrb.365.1584975080145; Mon, 23 Mar 2020 07:51:20 -0700 (PDT) X-Google-Smtp-Source: ADFU+vtv6CLGR/t9FJRgX3W/NJupPEZxVu8xP0RF001TVuZsrbyXW03jsERApw0prry/p+1nC0pqdg== X-Received: by 2002:adf:97c1:: with SMTP id t1mr30336537wrb.365.1584975079843; Mon, 23 Mar 2020 07:51:19 -0700 (PDT) Received: from vitty.brq.redhat.com (g-server-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id t21sm9456865wmt.43.2020.03.23.07.51.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Mar 2020 07:51:19 -0700 (PDT) From: Vitaly Kuznetsov To: Sean Christopherson , Paolo Bonzini Cc: Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Ben Gardon , Junaid Shahid , Liran Alon , Boris Ostrovsky , John Haxby , Miaohe Lin , Tom Lendacky Subject: Re: [PATCH v3 02/37] KVM: nVMX: Validate the EPTP when emulating INVEPT(EXTENT_CONTEXT) In-Reply-To: <20200320212833.3507-3-sean.j.christopherson@intel.com> References: <20200320212833.3507-1-sean.j.christopherson@intel.com> <20200320212833.3507-3-sean.j.christopherson@intel.com> Date: Mon, 23 Mar 2020 15:51:17 +0100 Message-ID: <871rpj9lay.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sean Christopherson writes: > Signal VM-Fail for the single-context variant of INVEPT if the specified > EPTP is invalid. Per the INEVPT pseudocode in Intel's SDM, it's subject > to the standard EPT checks: > > If VM entry with the "enable EPT" VM execution control set to 1 would > fail due to the EPTP value then VMfail(Invalid operand to INVEPT/INVVPID); > > Fixes: bfd0a56b90005 ("nEPT: Nested INVEPT") > Signed-off-by: Sean Christopherson > --- > arch/x86/kvm/vmx/nested.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > index 8578513907d7..f3774cef4fd4 100644 > --- a/arch/x86/kvm/vmx/nested.c > +++ b/arch/x86/kvm/vmx/nested.c > @@ -5156,8 +5156,12 @@ static int handle_invept(struct kvm_vcpu *vcpu) > } > > switch (type) { > - case VMX_EPT_EXTENT_GLOBAL: > case VMX_EPT_EXTENT_CONTEXT: > + if (!nested_vmx_check_eptp(vcpu, operand.eptp)) > + return nested_vmx_failValid(vcpu, > + VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID); I was going to ask "and we don't seem to check that current nested VMPTR is valid, how can we know that nested_vmx_failValid() is the right VMfail() to use" but then I checked our nested_vmx_failValid() and there is a fallback there: if (vmx->nested.current_vmptr == -1ull && !vmx->nested.hv_evmcs) return nested_vmx_failInvalid(vcpu); so this is a non-issue. My question, however, transforms into "would it make sense to introduce nested_vmx_fail() implementing the logic from SDM: VMfail(ErrorNumber): IF VMCS pointer is valid THEN VMfailValid(ErrorNumber); ELSE VMfailInvalid; FI; to assist an innocent reader of the code?" > + fallthrough; > + case VMX_EPT_EXTENT_GLOBAL: > /* > * TODO: Sync the necessary shadow EPT roots here, rather than > * at the next emulated VM-entry. Reviewed-by: Vitaly Kuznetsov -- Vitaly