From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 53701] New: nVMX: Unchecked setting of cr4 for nested guest Date: Tue, 12 Feb 2013 08:49:26 +0000 (UTC) Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" To: kvm@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.19.201]:55819 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758327Ab3BLItb (ORCPT ); Tue, 12 Feb 2013 03:49:31 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4B82620224 for ; Tue, 12 Feb 2013 08:49:30 +0000 (UTC) Received: from bugzilla.kernel.org (bugzilla.kernel.org [198.145.19.217]) by mail.kernel.org (Postfix) with ESMTP id 92F3020222 for ; Tue, 12 Feb 2013 08:49:27 +0000 (UTC) Sender: kvm-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=53701 Summary: nVMX: Unchecked setting of cr4 for nested guest Product: Virtualization Version: unspecified Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: enhancement Priority: P1 Component: kvm AssignedTo: virtualization_kvm@kernel-bugs.osdl.org ReportedBy: nyh@math.technion.ac.il Regression: No On 29 May 2012, Avi Kivity wrote on the KVM mailing list: It looks like the lines vmx_set_cr0(vcpu, vmcs12->guest_cr0); vmcs_writel(CR0_READ_SHADOW, nested_read_cr0(vmcs12)); vmx_set_cr4(vcpu, vmcs12->guest_cr4); vmcs_writel(CR4_READ_SHADOW, nested_read_cr4(vmcs12)); in prepare_vmcs02() are too dangerous. They only let the hardware check cr4, but not software, so a future cr4 bit which is not handled correctly by kvm can be set in a nested guest. L1 appears to be protected, we use kvm_set_cr4(). -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are watching the assignee of the bug.