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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH,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 D8FD2C433F5 for ; Sun, 2 Sep 2018 13:13:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 877B1205F4 for ; Sun, 2 Sep 2018 13:13:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=microsoft.com header.i=@microsoft.com header.b="IC11cpoY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 877B1205F4 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=microsoft.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729534AbeIBR3C (ORCPT ); Sun, 2 Sep 2018 13:29:02 -0400 Received: from mail-sn1nam02on0115.outbound.protection.outlook.com ([104.47.36.115]:45032 "EHLO NAM02-SN1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729234AbeIBRXW (ORCPT ); Sun, 2 Sep 2018 13:23:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=niPsq3BFlAydwYiM1h2XV2tCmJjccVlqwahi8ADwvyg=; b=IC11cpoYxBz/B9vpZEtPF0RPrUs/wwIKgZOiHF98ntnllVvGp+6rvlZXMjIFwBZhSRtm4rdkn5gFnEW+Ctw0gjhwH3Mz7IYWmbwY2EbPT1keVQC1pWEaAWlmZu1aOW4T5mSLqUo+sYq4iLiAkxDdKr7WmB2FN7bstd+jfyjszF8= Received: from CY4PR21MB0776.namprd21.prod.outlook.com (10.173.192.22) by CY4PR21MB0503.namprd21.prod.outlook.com (10.172.122.13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1122.2; Sun, 2 Sep 2018 13:07:14 +0000 Received: from CY4PR21MB0776.namprd21.prod.outlook.com ([fe80::7c3a:eea8:1391:1611]) by CY4PR21MB0776.namprd21.prod.outlook.com ([fe80::7c3a:eea8:1391:1611%7]) with mapi id 15.20.1143.000; Sun, 2 Sep 2018 13:07:14 +0000 From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Joerg Roedel , Thomas Gleixner , "H . Peter Anvin" , "linux-mm@kvack.org" , Linus Torvalds , Andy Lutomirski , Dave Hansen , Josh Poimboeuf , Juergen Gross , Peter Zijlstra , Borislav Petkov , Jiri Kosina , Boris Ostrovsky , Brian Gerst , David Laight , Denys Vlasenko , Eduardo Valentin , Greg KH , Will Deacon , "aliguori@amazon.com" , Daniel Gruss , "hughd@google.com" , "keescook@google.com" , Andrea Arcangeli , Waiman Long , Pavel Machek , Arnaldo Carvalho de Melo , Alexander Shishkin , Jiri Olsa , Namhyung Kim , "joro@8bytes.org" , Sasha Levin Subject: [PATCH AUTOSEL 4.14 48/89] x86/kexec: Allocate 8k PGDs for PTI Thread-Topic: [PATCH AUTOSEL 4.14 48/89] x86/kexec: Allocate 8k PGDs for PTI Thread-Index: AQHUQr3b5qaqnfY0ck+Kjj6okvOk8g== Date: Sun, 2 Sep 2018 13:07:10 +0000 Message-ID: <20180902064918.183387-48-alexander.levin@microsoft.com> References: <20180902064918.183387-1-alexander.levin@microsoft.com> In-Reply-To: <20180902064918.183387-1-alexander.levin@microsoft.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [52.168.54.252] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;CY4PR21MB0503;6:4NaEa6BgwEVX8hdwaqqUk9oT4dowU2mtZJYCW8+7Sj2yERs+ItEiMkYXWhumwbcsXe0qnxC0uZLrfP+CQZpPXxU4UrFlcZgUeNuUxX+I1kRHHwThPBwdvlOKND94Az13qd2DClFMaszM3tgmTN427lAmQTxpdUMiTlXqasp/+dIMvP9oYsiVDmzOKtHlvbBAqu52IcQ8RbjXk1v8MJAtYqUzsyz6sULn+kYSoQ0RDGIcWoesqz4yjgf3Ha+JuIvPjnl+HK5VaMdTAWLE+RJRUZh3qepz2iKEgCjXf5xK2YfGGTDjN4PEwtBoZTCyS+BekCWZjfGtJaEzvAREgsCYMV2fIyCdst+F9lX8L2xi+VEgfuXhmIqtiEU9t5oMNHqE5WmmN2J0hLFtyCv/+I5mJ6kZX+tg+kOIRobUQKdkarmcqE0ZJCivgjHEYJMpELDSEmKo8Odc58rNT0f1sRl0+g==;5:+duwnctfLoLeIw4XT8eSPcjIKrE1K/BMFX+9uaNc9rVYZLOBE7uG85DU+ggqwJcteMKaGiSaKX8XPxUDRstWw0QSJKjNFQ6jmImpvFX7qTsFxiWUnyTI5E7iCtDGkpOo1J3mIaZsR02AykTIIxSS/JY79b4sLk3B4OTxdGXTokk=;7:+bUdTTyjFog65zdx7BQjDnPONCdCBwZHfbftxR8xrXG3AlLIctRsbcWnReqE4n0UGmbIM8M6VI5f7lzP6FWUXupufPeIsV5S2NIZFNXDEp0Sf75/g/uu5MbFekLUXfnVlwYA7I6jhJc6CBGHTNe74dA74NbLRPmLB5GLHrXAwZ/DfwXRQTU9Qpf11qB2zeZgjqRi6B21faCoezjfJp3SLaZW983Htj//CLzT6P2cdGJmLBfpF+jnn9J7J9ku0IGu x-ms-office365-filtering-correlation-id: 2fa89296-8bd4-4337-cd84-08d610d5006d x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0;PCL:0;RULEID:(7020095)(4652040)(4534165)(4627221)(201703031133081)(201702281549075)(5600074)(711020)(4618075)(2017052603328)(7193020);SRVR:CY4PR21MB0503; x-ms-traffictypediagnostic: CY4PR21MB0503: x-ld-processed: 72f988bf-86f1-41af-91ab-2d7cd011db47,ExtAddr x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(20283166320243)(28532068793085)(180628864354917)(89211679590171)(33061846794335)(85827821059158)(211936372134217)(42068640409301)(146099531331640)(47284530071512); x-ms-exchange-senderadcheck: 1 x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(8211001083)(2017102700009)(2017102701064)(6040522)(2401047)(5005006)(8121501046)(2017102702064)(20171027021009)(20171027022009)(20171027023009)(20171027024009)(20171027025009)(20171027026009)(2017102703076)(93006095)(93001095)(10201501046)(3231340)(944501410)(52105095)(2018427008)(3002001)(6055026)(149027)(150027)(6041310)(20161123558120)(20161123562045)(20161123564045)(20161123560045)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(201708071742011)(7699049)(76991033);SRVR:CY4PR21MB0503;BCL:0;PCL:0;RULEID:;SRVR:CY4PR21MB0503; x-forefront-prvs: 078310077C x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(396003)(39860400002)(136003)(376002)(346002)(366004)(189003)(199004)(105586002)(8936002)(102836004)(6346003)(68736007)(2900100001)(6116002)(217873002)(186003)(36756003)(81156014)(81166006)(1076002)(99286004)(26005)(7406005)(5660300001)(7416002)(66066001)(6666003)(8676002)(54906003)(256004)(316002)(305945005)(22452003)(3846002)(10090500001)(7736002)(110136005)(14444005)(106356001)(2906002)(6506007)(10290500003)(2501003)(966005)(478600001)(2616005)(72206003)(6512007)(53936002)(86362001)(39060400002)(86612001)(107886003)(6436002)(14454004)(76176011)(486006)(25786009)(476003)(97736004)(446003)(11346002)(6486002)(4326008)(6306002)(5250100002);DIR:OUT;SFP:1102;SCL:1;SRVR:CY4PR21MB0503;H:CY4PR21MB0776.namprd21.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;MX:1;A:1; received-spf: None (protection.outlook.com: microsoft.com does not designate permitted sender hosts) authentication-results: spf=none (sender IP is ) smtp.mailfrom=Alexander.Levin@microsoft.com; x-microsoft-antispam-message-info: JWErkMTo1u9SUMsL0pSgErPu9MY1ZlNWabeP3WcKrg7d7UK2XXR4oBnkBEiUkmaCt5wIookhxP8VS/7mGU1kPpnNXhwA83THiocUdyv61m6TEnMdQlmUNkXhXTYEhCwm8FEKxAY5ziiPviBoNu1tGEkl1sPkHbBzrEK5KZB5SzBrs11j3WpL5YZHUWCg145V75uiqEzX/Pf9qRgVjjdN0y9NhuwN2oWk3OJys7GYESMsl85MCAICdtt72yNQ4SXINhUpBe0hVEc4NuQwbCn7v+bXVXo7RPdpqlzciDUmd8c7OraqpWYRqpJ1o/0oCbJIpC7CPkdxhbovt7RwCUvTj2Miymc7cviO+XODQ4DyZTI= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2fa89296-8bd4-4337-cd84-08d610d5006d X-MS-Exchange-CrossTenant-originalarrivaltime: 02 Sep 2018 13:07:10.1375 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR21MB0503 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Joerg Roedel [ Upstream commit ca38dc8f2724d101038b1205122c93a1c7f38f11 ] Fuzzing the PTI-x86-32 code with trinity showed unhandled kernel paging request oops-messages that looked a lot like silent data corruption. Lot's of debugging and testing lead to the kexec-32bit code, which is still allocating 4k PGDs when PTI is enabled. But since it uses native_set_pud() to build the page-table, it will unevitably call into __pti_set_user_pgtbl(), which writes beyond the allocated 4k page. Use PGD_ALLOCATION_ORDER to allocate PGDs in the kexec code to fix the issue. Signed-off-by: Joerg Roedel Signed-off-by: Thomas Gleixner Tested-by: David H. Gutteridge Cc: "H . Peter Anvin" Cc: linux-mm@kvack.org Cc: Linus Torvalds Cc: Andy Lutomirski Cc: Dave Hansen Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Peter Zijlstra Cc: Borislav Petkov Cc: Jiri Kosina Cc: Boris Ostrovsky Cc: Brian Gerst Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Cc: Andrea Arcangeli Cc: Waiman Long Cc: Pavel Machek Cc: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Cc: joro@8bytes.org Link: https://lkml.kernel.org/r/1532533683-5988-4-git-send-email-joro@8byte= s.org Signed-off-by: Sasha Levin --- arch/x86/kernel/machine_kexec_32.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/machine_kexec_32.c b/arch/x86/kernel/machine_k= exec_32.c index 5167f3f74136..83cb5f3c72e5 100644 --- a/arch/x86/kernel/machine_kexec_32.c +++ b/arch/x86/kernel/machine_kexec_32.c @@ -56,7 +56,7 @@ static void load_segments(void) =20 static void machine_kexec_free_page_tables(struct kimage *image) { - free_page((unsigned long)image->arch.pgd); + free_pages((unsigned long)image->arch.pgd, PGD_ALLOCATION_ORDER); image->arch.pgd =3D NULL; #ifdef CONFIG_X86_PAE free_page((unsigned long)image->arch.pmd0); @@ -72,7 +72,8 @@ static void machine_kexec_free_page_tables(struct kimage = *image) =20 static int machine_kexec_alloc_page_tables(struct kimage *image) { - image->arch.pgd =3D (pgd_t *)get_zeroed_page(GFP_KERNEL); + image->arch.pgd =3D (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, + PGD_ALLOCATION_ORDER); #ifdef CONFIG_X86_PAE image->arch.pmd0 =3D (pmd_t *)get_zeroed_page(GFP_KERNEL); image->arch.pmd1 =3D (pmd_t *)get_zeroed_page(GFP_KERNEL); --=20 2.17.1