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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,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 C0D6FC0044C for ; Mon, 5 Nov 2018 05:21:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 799D320819 for ; Mon, 5 Nov 2018 05:21:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 799D320819 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.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 S1729156AbeKEOj3 convert rfc822-to-8bit (ORCPT ); Mon, 5 Nov 2018 09:39:29 -0500 Received: from mga18.intel.com ([134.134.136.126]:20549 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728918AbeKEOj2 (ORCPT ); Mon, 5 Nov 2018 09:39:28 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Nov 2018 21:21:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,466,1534834800"; d="scan'208";a="103431151" Received: from fmsmsx105.amr.corp.intel.com ([10.18.124.203]) by fmsmga004.fm.intel.com with ESMTP; 04 Nov 2018 21:21:38 -0800 Received: from shsmsx151.ccr.corp.intel.com (10.239.6.50) by FMSMSX105.amr.corp.intel.com (10.18.124.203) with Microsoft SMTP Server (TLS) id 14.3.408.0; Sun, 4 Nov 2018 21:21:37 -0800 Received: from shsmsx104.ccr.corp.intel.com ([169.254.5.117]) by SHSMSX151.ccr.corp.intel.com ([169.254.3.199]) with mapi id 14.03.0415.000; Mon, 5 Nov 2018 13:21:35 +0800 From: "Liu, Yi L" To: Lu Baolu , Joerg Roedel , David Woodhouse CC: "Raj, Ashok" , "linux-kernel@vger.kernel.org" , "iommu@lists.linux-foundation.org" Subject: RE: [PATCH 1/1] iommu/vtd: Fix NULL pointer dereference in prq_event_thread() Thread-Topic: [PATCH 1/1] iommu/vtd: Fix NULL pointer dereference in prq_event_thread() Thread-Index: AQHUdK5G5oGO3pmqp0mUcSJfurI3mKVAoM+A Date: Mon, 5 Nov 2018 05:21:35 +0000 Message-ID: References: <20181105021858.16958-1-baolu.lu@linux.intel.com> In-Reply-To: <20181105021858.16958-1-baolu.lu@linux.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-product: dlpe-windows dlp-version: 11.0.400.15 dlp-reaction: no-action x-ctpclassification: CTP_NT x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiMzZlODNmYzUtYmRjZS00ZTJhLWFjMjUtMGNhMGQ5YTYwZjk1IiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoick1uMTFUVVFRYjdSV0xya3NSTDZueW9SMW1rQStrcXpyNGpcLzVsWXhDbThLa3c3endlYnI1djVLY0o0Z2ZpRWgifQ== x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Baolu, > From: iommu-bounces@lists.linux-foundation.org [mailto:iommu- > bounces@lists.linux-foundation.org] On Behalf Of Lu Baolu > Sent: Monday, November 5, 2018 10:19 AM > To: Joerg Roedel ; David Woodhouse > Cc: Raj, Ashok ; linux-kernel@vger.kernel.org; > iommu@lists.linux-foundation.org > Subject: [PATCH 1/1] iommu/vtd: Fix NULL pointer dereference in prq_event_thread() > > When handling page request without pasid event, go to "no_pasid" > branch instead of "bad_req". Otherwise, a NULL pointer deference will happen there. > > Cc: Ashok Raj > Cc: Jacob Pan > Cc: Sohil Mehta > Signed-off-by: Lu Baolu > --- > drivers/iommu/intel-svm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index > db301efe126d..887150907526 100644 > --- a/drivers/iommu/intel-svm.c > +++ b/drivers/iommu/intel-svm.c > @@ -595,7 +595,7 @@ static irqreturn_t prq_event_thread(int irq, void *d) > pr_err("%s: Page request without PASID: %08llx %08llx\n", > iommu->name, ((unsigned long long *)req)[0], > ((unsigned long long *)req)[1]); > - goto bad_req; > + goto no_pasid; > } > > if (!svm || svm->pasid != req->pasid) { > -- I'm afraid it is still necessary to goto "bad_req". The following code behind "bad_req" will trigger fault_cb registered by in-kernel drivers. It is reasonable that PRQ without PASID can be handled by such callbacks. So I would suggest to keep the existing logic. if (sdev && sdev->ops && sdev->ops->fault_cb) { int rwxp = (req->rd_req << 3) | (req->wr_req << 2) | (req->exe_req << 1) | (req->priv_req); sdev->ops->fault_cb(sdev->dev, req->pasid, req->addr, req->private, rwxp, result); } Thanks, Yi Liu