From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3689844-1523235458-2-8705001563202369765 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='com', MailFrom='org', XOriginatingCountry='US' X-Spam-charsets: plain='iso-8859-1' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=fm2; t= 1523235457; b=XS6w3h2csu8HRx5uy3hYXLkKz8CqPoz3w+unzc1nsbYdco4TdR 4w68zOrQwJj89OMd2+YDVnZgj1K1gEXPWbsUDqpIWIySqupo9dv+bu5QNQAYAGrN /qut4NFOUfJ54TUrLjfpafGZGGGdieXkDmY6fPhR3p1zJZhicWmVK0QSrXgBl5il GcgaJZgrfrVQUGK2B2XT35F3+0nTy/5j9dMkuIHHOn9GghYLUGuSkipp39UhBuZk v9ZMxQFnWgZN2RWRQlCRdUfDD5Xg9dGQraNVe68aEEHzm0OZx/RGm8KRkfDGCdbA Ae7tI6+X2MkuoSI9klbe3GqNpxv5pHhF4kMQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :references:in-reply-to:content-type:content-transfer-encoding :mime-version:sender:list-id; s=fm2; t=1523235457; bh=77KC8siWkU Ft1USCJ6Rc2a1UuK2mPENgUFs68G3LhmE=; b=XlqWpE2WLDrYXW21DXScVrTR6M imrpwl6bsQVvLkfhQL2rqJOk1uMN1pm1Ja7Ga7Ql/sG8BEV8D+ye0EUH46qtuLuI Qyr7xrKVYlAWIARv92nWUAVIB5/5JQOyYSFd1/kjQOX3sH9TBHIGcfVOpr3EGvM1 pt8/lCChxKXfqhoJ10IsaZjTx4QsN4kFozsbPM3q5oecp7rfp+yG6T6EVeDPpJoD EFBzNTb+Wnavb1yOBFtroPoyHqOqYR+aPTbNPDFVgHuZShzsEO6NpjEqc4ViY7F+ f+4kTT1kqftcNo5lfySIUphXcQ7d7rWwy4UXSvPzpSesONLC1/R9WAdXVx6w== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=pass (1024-bit rsa key sha256) header.d=microsoft.com header.i=@microsoft.com header.b=EyaicNWn x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=selector1; dmarc=pass (p=reject,has-list-id=yes,d=none) header.from=microsoft.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=microsoft.com header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=pass (1024-bit rsa key sha256) header.d=microsoft.com header.i=@microsoft.com header.b=EyaicNWn x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=selector1; dmarc=pass (p=reject,has-list-id=yes,d=none) header.from=microsoft.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=microsoft.com header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean X-CM-Envelope: MS4wfIlqEAcTxrXiWWy8z7YsbyLEmqKLmy0x6OsYc1l5+kngM69xPtz20oC4dAbXmrAgKQhG0MIaWQaBHtRvqiA1e8XmUdi2RiqivrKr40aNJk8H3NkY3r1W wloyUyts81IxYXm42Y4TLLkuOeMgP2bvJu0YTBeH0dzQxgcT/b13FrbXaYkrQcaPT6vEh8Kb4CN+WNieIr2QvS0fBeQe0FTadn4X9xJP9wOhSI/8p9BVYT/z X-CM-Analysis: v=2.3 cv=WaUilXpX c=1 sm=1 tr=0 a=UK1r566ZdBxH71SXbqIOeA==:117 a=UK1r566ZdBxH71SXbqIOeA==:17 a=wRwT6uffUbIA:10 a=t_PdEiP4ckcA:10 a=mw6kJ3eo-EIA:10 a=8nJEP1OIZ-IA:10 a=xqWC_Br6kY4A:10 a=Kd1tUaAdevIA:10 a=Lf-vpJhqX20A:10 a=yPCof4ZbAAAA:8 a=VwQbUJbxAAAA:8 a=3DfWnJiXAAAA:8 a=1XWaLZrsAAAA:8 a=yMhMjlubAAAA:8 a=RYVZukao_CL1VzEAM68A:9 a=HWdR42TzdO_JRGdj:21 a=jE8EpxlFV5R1BAVH:21 a=wPNLvfGTeEIA:10 a=AjGcO6oz07-iQ99wixmX:22 a=fbZbCd7XTi_oNd1tYRxB:22 X-ME-CMScore: 0 X-ME-CMCategory: none Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932943AbeDIAkS (ORCPT ); Sun, 8 Apr 2018 20:40:18 -0400 Received: from mail-sn1nam01on0132.outbound.protection.outlook.com ([104.47.32.132]:41805 "EHLO NAM01-SN1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932553AbeDIAkP (ORCPT ); Sun, 8 Apr 2018 20:40:15 -0400 From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Christoph Hellwig , Bjorn Helgaas , Sasha Levin Subject: [PATCH AUTOSEL for 3.18 031/101] PCI: Protect pci_error_handlers->reset_notify() usage with device_lock() Thread-Topic: [PATCH AUTOSEL for 3.18 031/101] PCI: Protect pci_error_handlers->reset_notify() usage with device_lock() Thread-Index: AQHTz5qv6OsF1ho/pEyaKasZk+s2yg== Date: Mon, 9 Apr 2018 00:35:40 +0000 Message-ID: <20180409003505.164715-31-alexander.levin@microsoft.com> References: <20180409003505.164715-1-alexander.levin@microsoft.com> In-Reply-To: <20180409003505.164715-1-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;DM5PR2101MB0966;7:zFY3M2flnHCShoNHlH2lebyB3vZxJccmcftOUVpcyNiRFdGypTSLeEK0UXqVKxm29MxVfM7pSH3uLhHRyv618Kvg26Z7YfWKUHwOaK6qV59R+t4nCInhQrQEQjbbUeF0bmsnqZ1fjYWzvS/cPdyRhdR2O6PuyNU6sS3YOw7mcFbSTOYH5Rp6+H8fuiKqCGUjf1TdFGFmcmMwWLzrvZW96MXE0WfeuAuflQ8TRW7Xx15U8jlX5ak1+lh7rUCvG3q0;20:xSNu3LHrxm/xszi7RxIlMd0DkOYkEnj8goFPpOOJoNPpzE8CaKcYo1XGjLVrFlYW2YN8h+7irPmYBHuzJMyfLghp61cb4AcefcBkoRHF68OlesUGzUnEDL7Tk7Gbhw9nyLWu64jG0zq3l1shUL9913g5KizjWfWGOy9MIySURsE= x-ms-office365-filtering-ht: Tenant X-MS-Office365-Filtering-Correlation-Id: fe95ec3f-c134-4120-89cd-08d59db27577 x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:(7020095)(4652020)(48565401081)(5600026)(4604075)(3008032)(4534165)(4627221)(201703031133081)(201702281549075)(2017052603328)(7193020);SRVR:DM5PR2101MB0966; x-ms-traffictypediagnostic: DM5PR2101MB0966: authentication-results: spf=none (sender IP is ) smtp.mailfrom=Alexander.Levin@microsoft.com; x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(28532068793085)(89211679590171)(211936372134217)(42068640409301)(153496737603132)(146099531331640)(17755550239193); x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(8211001083)(61425038)(6040522)(2401047)(5005006)(8121501046)(93006095)(93001095)(3231221)(944501327)(52105095)(3002001)(10201501046)(6055026)(61426038)(61427038)(6041310)(20161123558120)(20161123562045)(20161123560045)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(20161123564045)(6072148)(201708071742011);SRVR:DM5PR2101MB0966;BCL:0;PCL:0;RULEID:;SRVR:DM5PR2101MB0966; x-forefront-prvs: 0637FCE711 x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(366004)(396003)(39380400002)(376002)(346002)(39860400002)(189003)(199004)(54534003)(5660300001)(26005)(6116002)(305945005)(3846002)(2616005)(68736007)(72206003)(86612001)(476003)(446003)(36756003)(66066001)(2501003)(575784001)(99286004)(86362001)(478600001)(11346002)(7736002)(105586002)(3280700002)(97736004)(14454004)(110136005)(2906002)(54906003)(4326008)(3660700001)(6486002)(8936002)(486006)(22452003)(10290500003)(6506007)(81166006)(6436002)(316002)(6512007)(59450400001)(6666003)(6306002)(966005)(2900100001)(186003)(76176011)(8676002)(10090500001)(107886003)(5250100002)(81156014)(1076002)(25786009)(106356001)(53936002)(102836004)(22906009)(217873001);DIR:OUT;SFP:1102;SCL:1;SRVR:DM5PR2101MB0966;H:DM5PR2101MB1032.namprd21.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;MX:1;A:1; x-microsoft-antispam-message-info: q7hcxZX/iR/oSgN/CAx4TgQLxyNCWC03gMCS2OoXfayGUQGtP+HpcDH1A3wg7HmogisOrpLOdVF+sFKRwx/KJI3Gpm0E39oEwQQonChD+wM9c3tIwIPFdVEXmqvDzPwC1LFhLSIn40D/oBOfMUx57ZjCdQlB4G/bOJuFGGx9mBbmxQIV/XRBOj+Q61jkRksBiTDv8ilDVJGjtLkAbgVAbyPFJ/gp6BusTv4h+/u9EL/GFwT9eQIF+kY52ZloeBlmQMrRAuxavvHxjv8JDuwaOIsQ0h9dprGh/1dmlmInZ6XFPagVtTFRmyWAFNc8FgPpNGxe4GpyKwt9/V0LVRBajEKYEKf8HOFrM0QrlGJ8m14yh+u0WyLvZBHYYFu8spnN0gCbZVk/dnjufPjUp9tQMhR8xQuM1GEXJhqOBbxLyX0= 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: fe95ec3f-c134-4120-89cd-08d59db27577 X-MS-Exchange-CrossTenant-originalarrivaltime: 09 Apr 2018 00:35:40.0485 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM5PR2101MB0966 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: From: Christoph Hellwig [ Upstream commit b014e96d1abbd67404bbe2018937b46466299e9e ] Every method in struct device_driver or structures derived from it like struct pci_driver MUST provide exclusion vs the driver's ->remove() method, usually by using device_lock(). Protect use of pci_error_handlers->reset_notify() by holding the device lock while calling it. Note: - pci_dev_lock() calls device_lock() in addition to blocking user-space config accesses. - pci_err_handlers->reset_notify() is used inside pci_dev_save_and_disable() and pci_dev_restore(). We could hold the device lock directly in pci_reset_notify(), but we expand the region since we have several calls following each other. Without this, ->reset_notify() may race with ->remove() calls, which can be easily triggered in NVMe. [bhelgaas: changelog, add pci_reset_notify() comment] [bhelgaas: fold in fix from Dan Carpenter : http://lkml.kernel.org/r/20170701135323.x5vaj4e2wcs2mcro@mwanda] Link: http://lkml.kernel.org/r/20170601111039.8913-2-hch@lst.de Reported-by: Rakesh Pandit Tested-by: Rakesh Pandit Signed-off-by: Christoph Hellwig Signed-off-by: Bjorn Helgaas Signed-off-by: Sasha Levin --- drivers/pci/pci.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 1563cfadeaef..3f8d4c0c997c 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3402,6 +3402,12 @@ static void pci_reset_notify(struct pci_dev *dev, bo= ol prepare) { const struct pci_error_handlers *err_handler =3D dev->driver ? dev->driver->err_handler : NULL; + + /* + * dev->driver->err_handler->reset_notify() is protected against + * races with ->remove() by the device lock, which must be held by + * the caller. + */ if (err_handler && err_handler->reset_notify) err_handler->reset_notify(dev, prepare); } @@ -3537,11 +3543,13 @@ int pci_reset_function(struct pci_dev *dev) if (rc) return rc; =20 + pci_dev_lock(dev); pci_dev_save_and_disable(dev); =20 - rc =3D pci_dev_reset(dev, 0); + rc =3D __pci_dev_reset(dev, 0); =20 pci_dev_restore(dev); + pci_dev_unlock(dev); =20 return rc; } @@ -3561,16 +3569,14 @@ int pci_try_reset_function(struct pci_dev *dev) if (rc) return rc; =20 - pci_dev_save_and_disable(dev); + if (!pci_dev_trylock(dev)) + return -EAGAIN; =20 - if (pci_dev_trylock(dev)) { - rc =3D __pci_dev_reset(dev, 0); - pci_dev_unlock(dev); - } else - rc =3D -EAGAIN; + pci_dev_save_and_disable(dev); + rc =3D __pci_dev_reset(dev, 0); + pci_dev_unlock(dev); =20 pci_dev_restore(dev); - return rc; } EXPORT_SYMBOL_GPL(pci_try_reset_function); @@ -3724,7 +3730,9 @@ static void pci_bus_save_and_disable(struct pci_bus *= bus) struct pci_dev *dev; =20 list_for_each_entry(dev, &bus->devices, bus_list) { + pci_dev_lock(dev); pci_dev_save_and_disable(dev); + pci_dev_unlock(dev); if (dev->subordinate) pci_bus_save_and_disable(dev->subordinate); } @@ -3739,7 +3747,9 @@ static void pci_bus_restore(struct pci_bus *bus) struct pci_dev *dev; =20 list_for_each_entry(dev, &bus->devices, bus_list) { + pci_dev_lock(dev); pci_dev_restore(dev); + pci_dev_unlock(dev); if (dev->subordinate) pci_bus_restore(dev->subordinate); } --=20 2.15.1