From patchwork Thu Oct 12 11:59:48 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 10001753 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 27AEB6028A for ; Thu, 12 Oct 2017 12:00:55 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1BEBB28D3B for ; Thu, 12 Oct 2017 12:00:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 10DE628D87; Thu, 12 Oct 2017 12:00:55 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_SPAM, T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C1FDC28D3B for ; Thu, 12 Oct 2017 12:00:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756779AbdJLMA0 (ORCPT ); Thu, 12 Oct 2017 08:00:26 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:55861 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752095AbdJLL75 (ORCPT ); Thu, 12 Oct 2017 07:59:57 -0400 Received: by mail-wm0-f65.google.com with SMTP id u138so12731070wmu.4; Thu, 12 Oct 2017 04:59:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=GtkP3AfbrV7Ajq9AFwPrzJbTEgqDH5WDorj75CEYITE=; b=cPio7IQgWMC3+Ud8KG7ZQ2lMfchpU00Wy6OUum8VZDGy3X4e8pDPo3F7/+OTiS+s4R FB3cTaiXHtzYGanu8mEM0AGqk6mAkqKgG3pxGHsb9MdVqi/cBqw9q7bQJF2dPV0jLfio RxiBN7E9mTIxXyX2dnuaHSEa/b7/naOTzcsr6zAf8o7SY7aoRitH/GyEu5kHtdUY6X8/ 7zTFFL/3riqZeG9NwMGuQJlRtILO65HYXC1M29gywWS0qP/8izzqlOAxCrI6y+xC97pX LQntw8dLog6Y7+FYeH4zCKRhWre9gnZ575aElDlvd1Xcwad/0usXnwqZuUlJoUIzgIo+ bFhw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references; bh=GtkP3AfbrV7Ajq9AFwPrzJbTEgqDH5WDorj75CEYITE=; b=Hwm30nAC1b8axwnHyxeuUytda1MhehR0iUMTIBIrjRiPJBSa/cVOGwBtltmL9KCfJK zMnHBaAg0iwSKzOvvFuuKwe3CILO7j8iWfhI0WEtwq7I5/ptDK71YOuZ6yYKGlgACfh0 QA6xnWQFP9kBTxoRnEcka7oVRFT0XqPviA58XEJPYIyx6RyOS55Y60hR4lxQgUOscHWY LsJWK5QvcbmcYYYoasmjxTfx4Mbj17/3mugj2YC4xnUy1Oh9E2KqrDQBKMDqlznNkygO shKIrv9UOljptRxDzYTIjzHH1XL3TokXd9DyTkOrADSipkMOII52Xm48UuMkX2nkUqdv zzyA== X-Gm-Message-State: AMCzsaWfHvhSPlWELT82VCx8CPQxz/ekfIHL06yDSrUMn2mwRhjBkN+K tSqNciPLdcxQkrPUKTlqrt0NnUSc X-Google-Smtp-Source: ABhQp+Rw6AgREmKWI7iKE13xBIRos+/+8Il29EZGcI4DCbva2n7Up/PLOuX7XcIXB7/ENO7hiyUCSw== X-Received: by 10.28.143.203 with SMTP id r194mr1868548wmd.39.1507809595716; Thu, 12 Oct 2017 04:59:55 -0700 (PDT) Received: from 640k.lan (94-36-246-2.adsl-ull.clienti.tiscali.it. [94.36.246.2]) by smtp.gmail.com with ESMTPSA id y23sm12326471wry.62.2017.10.12.04.59.54 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 12 Oct 2017 04:59:55 -0700 (PDT) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Ladi Prosek Subject: [PATCH 1/2] KVM: nVMX: update last_nonleaf_level when initializing nested EPT Date: Thu, 12 Oct 2017 13:59:48 +0200 Message-Id: <1507809589-12786-2-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1507809589-12786-1-git-send-email-pbonzini@redhat.com> References: <1507809589-12786-1-git-send-email-pbonzini@redhat.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Ladi Prosek The function updates context->root_level but didn't call update_last_nonleaf_level so the previous and potentially wrong value was used for page walks. For example, a zero value of last_nonleaf_level would allow a potential out-of-bounds access in arch/x86/mmu/paging_tmpl.h's walk_addr_generic function (CVE-2017-12188). Fixes: 155a97a3d7c78b46cef6f1a973c831bc5a4f82bb Signed-off-by: Ladi Prosek Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 106d4a029a8a..3c25f20115bc 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -4555,6 +4555,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, update_permission_bitmask(vcpu, context, true); update_pkru_bitmask(vcpu, context, true); + update_last_nonleaf_level(vcpu, context); reset_rsvds_bits_mask_ept(vcpu, context, execonly); reset_ept_shadow_zero_bits_mask(vcpu, context, execonly); }