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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 17CBBECDE5F for ; Mon, 23 Jul 2018 04:20:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2EBE120858 for ; Mon, 23 Jul 2018 04:20:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2EBE120858 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zte.com.cn 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 S1728113AbeGWFTx (ORCPT ); Mon, 23 Jul 2018 01:19:53 -0400 Received: from mxhk.zte.com.cn ([63.217.80.70]:14052 "EHLO mxhk.zte.com.cn" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726669AbeGWFTx (ORCPT ); Mon, 23 Jul 2018 01:19:53 -0400 Received: from mse01.zte.com.cn (unknown [10.30.3.20]) by Forcepoint Email with ESMTPS id 8835A15ADD7795D3C508; Mon, 23 Jul 2018 12:20:36 +0800 (CST) Received: from notes_smtp.zte.com.cn ([10.30.1.239]) by mse01.zte.com.cn with ESMTP id w6N4KPek046097; Mon, 23 Jul 2018 12:20:25 +0800 (GMT-8) (envelope-from wang.yi59@zte.com.cn) Received: from fox-host8.localdomain ([10.74.120.8]) by szsmtp06.zte.com.cn (Lotus Domino Release 8.5.3FP6) with ESMTP id 2018072312202698-1250143 ; Mon, 23 Jul 2018 12:20:26 +0800 From: Yi Wang To: mingo@redhat.com Cc: peterz@infradead.org, linux-kernel@vger.kernel.org, jiang.biao2@zte.com.cn, wang.yi59@zte.com.cn, zhong.weidong@zte.com.cn Subject: [PATCH] sched/topology: check variable group before dereferenced Date: Mon, 23 Jul 2018 12:19:07 +0800 Message-Id: <1532319547-33335-1-git-send-email-wang.yi59@zte.com.cn> X-Mailer: git-send-email 1.8.3.1 X-MIMETrack: Itemize by SMTP Server on SZSMTP06/server/zte_ltd(Release 8.5.3FP6|November 21, 2013) at 2018-07-23 12:20:27, Serialize by Router on notes_smtp/zte_ltd(Release 9.0.1FP7|August 17, 2016) at 2018-07-23 12:20:25, Serialize complete at 2018-07-23 12:20:25 X-MAIL: mse01.zte.com.cn w6N4KPek046097 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The variable group in sched_domain_debug_one() is not checked when firstly used in cpumask_test_cpu(cpu, sched_group_span(group)), but it maybe NULL(checked later in the following while loop) and may cause NULL pointer dereference without checking. We need to check it before using to avoid NULL dereference. Signed-off-by: Yi Wang Reviewed-by: Jiang Biao --- kernel/sched/topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 5ac724b..c7cf87c 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -53,7 +53,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, printk(KERN_ERR "ERROR: domain->span does not contain " "CPU%d\n", cpu); } - if (!cpumask_test_cpu(cpu, sched_group_span(group))) { + if (group && !cpumask_test_cpu(cpu, sched_group_span(group))) { printk(KERN_ERR "ERROR: domain->groups does not contain" " CPU%d\n", cpu); } -- 1.8.3.1