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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 1241EC2BA19 for ; Tue, 14 Apr 2020 15:10:14 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C6A8E2087E for ; Tue, 14 Apr 2020 15:10:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C6A8E2087E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 2A5938E001F; Tue, 14 Apr 2020 11:10:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 22EAC8E0007; Tue, 14 Apr 2020 11:10:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0F8888E001F; Tue, 14 Apr 2020 11:10:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0041.hostedemail.com [216.40.44.41]) by kanga.kvack.org (Postfix) with ESMTP id E7C6C8E0007 for ; Tue, 14 Apr 2020 11:10:12 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id A04F33ABC for ; Tue, 14 Apr 2020 15:10:12 +0000 (UTC) X-FDA: 76706796264.03.sand78_1c2359017218 X-HE-Tag: sand78_1c2359017218 X-Filterd-Recvd-Size: 3934 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by imf13.hostedemail.com (Postfix) with ESMTP for ; Tue, 14 Apr 2020 15:10:11 +0000 (UTC) Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 03EF4JHi063818 for ; Tue, 14 Apr 2020 11:10:11 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0b-001b2d01.pphosted.com with ESMTP id 30dc3rfhx2-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 14 Apr 2020 11:10:11 -0400 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 14 Apr 2020 16:10:05 +0100 Received: from b06cxnps3074.portsmouth.uk.ibm.com (9.149.109.194) by e06smtp07.uk.ibm.com (192.168.101.137) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 14 Apr 2020 16:10:01 +0100 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 03EFA4Pi32243872 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 14 Apr 2020 15:10:04 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BCCBA42052; Tue, 14 Apr 2020 15:10:04 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 748BA4204C; Tue, 14 Apr 2020 15:10:04 +0000 (GMT) Received: from oc3871087118.ibm.com (unknown [9.145.30.155]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 14 Apr 2020 15:10:04 +0000 (GMT) From: Alexander Gordeev To: linux-kernel@vger.kernel.org Cc: Alexander Gordeev , "Kirill A. Shutemov" , linux-mm@kvack.org Subject: [PATCH] mm/gup: dereference page table entry using helper Date: Tue, 14 Apr 2020 17:10:01 +0200 X-Mailer: git-send-email 1.8.3.1 X-TM-AS-GCONF: 00 x-cbid: 20041415-0028-0000-0000-000003F8251A X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20041415-0029-0000-0000-000024BDD32C Message-Id: <1586877001-19138-1-git-send-email-agordeev@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.676 definitions=2020-04-14_06:2020-04-14,2020-04-14 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 mlxscore=0 clxscore=1015 spamscore=0 mlxlogscore=869 lowpriorityscore=0 phishscore=0 bulkscore=0 impostorscore=0 suspectscore=1 adultscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004140119 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Commit 0005d20 ("mm/gup: Move page table entry dereference into helper function") wrapped access to page table entries larger than sizeof(long) into a race-aware accessor. One of the two dereferences in gup_fast path was however overlooked. CC: Kirill A. Shutemov CC: linux-mm@kvack.org Signed-off-by: Alexander Gordeev --- mm/gup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/gup.c b/mm/gup.c index d53f7dd..eceb98b 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2208,7 +2208,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, if (!head) goto pte_unmap; - if (unlikely(pte_val(pte) != pte_val(*ptep))) { + if (unlikely(pte_val(pte) != pte_val(gup_get_pte(ptep)))) { put_compound_head(head, 1, flags); goto pte_unmap; } -- 1.8.3.1