From patchwork Thu Sep 22 06:38:22 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Beulich X-Patchwork-Id: 9344543 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 5AD25601C2 for ; Thu, 22 Sep 2016 06:41:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 440BB2A54A for ; Thu, 22 Sep 2016 06:41:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 350642A556; Thu, 22 Sep 2016 06:41:02 +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=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id AF6AB2A54A for ; Thu, 22 Sep 2016 06:41:01 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bmxeO-0005lC-Dx; Thu, 22 Sep 2016 06:38:28 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bmxeN-0005l6-5A for xen-devel@lists.xenproject.org; Thu, 22 Sep 2016 06:38:27 +0000 Received: from [85.158.137.68] by server-5.bemta-3.messagelabs.com id 43/20-03281-26C73E75; Thu, 22 Sep 2016 06:38:26 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrIIsWRWlGSWpSXmKPExsXS6fjDSzex5nG 4wZVuXYvvWyYzOTB6HP5whSWAMYo1My8pvyKBNeNc83/mguXCFQeOrWRpYDzM18XIySEkkCex 7dpNZhCbV8BO4nv/YnYQW0LAUOLp++tsIDaLgKpEW+NZVhCbTUBdou3ZdiCbg0NEwEDi3NEkE JNZQF9i2zoWkAphAWuJ+08eMIGEeQUEJf7uEIaosJNYe15hAiPXLITELITELKBWZgEtiYe/br FA2NoSyxa+ZoYokZZY/o8DImwm8fTLXGZUJSC2o8SVe+fZFjByrGJUL04tKkst0jXSSyrKTM8 oyU3MzNE1NDDWy00tLk5MT81JTCrWS87P3cQIDLp6BgbGHYynmp0PMUpyMCmJ8l4oehwuxJeU n1KZkVicEV9UmpNafIhRhoNDSYL3URVQTrAoNT21Ii0zBxj+MGkJDh4lEV7ZaqA0b3FBYm5xZ jpE6hSjopQ4Ly9IQgAkkVGaB9cGi7lLjLJSwryMDAwMQjwFqUW5mSWo8q8YxTkYlYR5t4Js58 nMK4Gb/gpoMRPQ4i0/H4AsLklESEk1MC7Pf3t54ybmFzMvWH/nWlHDofqrmevCzc8u7lz2qsK v/SamHZGY4t11ToqvNCjs6z37ea2rkr/P8SypLW1eay6o8zR1UsDHkIinVo0sYrIflcuWFs0x /bnHcsmOIye8j24wUud6enbW86a0S6IRTsbKT128GGSSS0OauT5E2k13eygQon7glRJLcUaio RZzUXEiAAcxJv+0AgAA X-Env-Sender: JBeulich@suse.com X-Msg-Ref: server-6.tower-31.messagelabs.com!1474526303!35691731!1 X-Originating-IP: [137.65.248.74] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 8.84; banners=-,-,- X-VirusChecked: Checked Received: (qmail 12441 invoked from network); 22 Sep 2016 06:38:25 -0000 Received: from prv-mh.provo.novell.com (HELO prv-mh.provo.novell.com) (137.65.248.74) by server-6.tower-31.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 22 Sep 2016 06:38:25 -0000 Received: from INET-PRV-MTA by prv-mh.provo.novell.com with Novell_GroupWise; Thu, 22 Sep 2016 00:38:23 -0600 Message-Id: <57E3987E020000780011162A@prv-mh.provo.novell.com> X-Mailer: Novell GroupWise Internet Agent 14.2.1 Date: Thu, 22 Sep 2016 00:38:22 -0600 From: "Jan Beulich" To: "xen-devel" Mime-Version: 1.0 Cc: Andrew Cooper Subject: [Xen-devel] [PATCH] x86emul: don't allow null selector for LTR X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP Signed-off-by: Jan Beulich Reviewed-by: Konrad Rzeszutek Wilk Reviewed-by: Andrew Cooper --- This goes on top of https://lists.xenproject.org/archives/html/xen-devel/2016-09/msg02198.html x86emul: don't allow null selector for LTR Signed-off-by: Jan Beulich --- This goes on top of https://lists.xenproject.org/archives/html/xen-devel/2016-09/msg02198.html --- a/xen/arch/x86/x86_emulate/x86_emulate.c +++ b/xen/arch/x86/x86_emulate/x86_emulate.c @@ -1207,10 +1207,17 @@ protmode_load_seg( /* NULL selector? */ if ( (sel & 0xfffc) == 0 ) { - if ( (seg == x86_seg_cs) || - ((seg == x86_seg_ss) && - (!mode_64bit() || (cpl == 3) || (cpl != sel))) ) + switch ( seg ) + { + case x86_seg_ss: + if ( mode_64bit() && (cpl != 3) && (cpl == sel) ) + default: + break; + /* fall through */ + case x86_seg_cs: + case x86_seg_tr: goto raise_exn; + } memset(sreg, 0, sizeof(*sreg)); sreg->sel = sel; return X86EMUL_OKAY; --- a/xen/arch/x86/x86_emulate/x86_emulate.c +++ b/xen/arch/x86/x86_emulate/x86_emulate.c @@ -1207,10 +1207,17 @@ protmode_load_seg( /* NULL selector? */ if ( (sel & 0xfffc) == 0 ) { - if ( (seg == x86_seg_cs) || - ((seg == x86_seg_ss) && - (!mode_64bit() || (cpl == 3) || (cpl != sel))) ) + switch ( seg ) + { + case x86_seg_ss: + if ( mode_64bit() && (cpl != 3) && (cpl == sel) ) + default: + break; + /* fall through */ + case x86_seg_cs: + case x86_seg_tr: goto raise_exn; + } memset(sreg, 0, sizeof(*sreg)); sreg->sel = sel; return X86EMUL_OKAY;