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=-12.8 required=3.0 tests=BAYES_00, 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 AA6BFC433E7 for ; Thu, 15 Oct 2020 12:16:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 510122223F for ; Thu, 15 Oct 2020 12:16:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726785AbgJOMQE (ORCPT ); Thu, 15 Oct 2020 08:16:04 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:15219 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726103AbgJOMQE (ORCPT ); Thu, 15 Oct 2020 08:16:04 -0400 Received: from DGGEMS411-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id BB12D79062E39210F1E9; Thu, 15 Oct 2020 20:16:00 +0800 (CST) Received: from huawei.com (10.175.104.175) by DGGEMS411-HUB.china.huawei.com (10.3.19.211) with Microsoft SMTP Server id 14.3.487.0; Thu, 15 Oct 2020 20:15:51 +0800 From: Shijie Luo To: CC: , , , , Subject: [PATCH] mm: fix potential pte_unmap_unlock pte error Date: Thu, 15 Oct 2020 08:15:34 -0400 Message-ID: <20201015121534.50910-1-luoshijie1@huawei.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.104.175] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When flags don't have MPOL_MF_MOVE or MPOL_MF_MOVE_ALL bits, code breaks and passing origin pte - 1 to pte_unmap_unlock seems like not a good idea. Signed-off-by: Shijie Luo Signed-off-by: linmiaohe --- mm/mempolicy.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 3fde772ef5ef..01f088630d1d 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -571,7 +571,11 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr, } else break; } - pte_unmap_unlock(pte - 1, ptl); + + if (addr >= end) + pte = pte - 1; + + pte_unmap_unlock(pte, ptl); cond_resched(); if (has_unmovable) -- 2.19.1