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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 600D3C38161 for ; Tue, 12 Apr 2022 07:33:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351843AbiDLHdS (ORCPT ); Tue, 12 Apr 2022 03:33:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42842 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354659AbiDLH0e (ORCPT ); Tue, 12 Apr 2022 03:26:34 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B2FDD4665C; Tue, 12 Apr 2022 00:06:26 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id E9F1EB81B5D; Tue, 12 Apr 2022 07:06:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B390C385AE; Tue, 12 Apr 2022 07:06:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649747183; bh=MIJOt/rCjVZ1I/G8JnoYtBGZqGnfCfzujr8/xisSegw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SPGqSLAfSorR1ulggq87bjrk22Vm21k+K2/vc927DfRSukaqCcAK4dVoWBZ+vsPnD moFJt3y/aihcd4uimzgRr/iczuxE5N1Wxb8vxU0d9eej1JHEqSZf/WrHHI/zd9axD9 lY8PIqlKEpJGrOWHvqUTif4aMSmWOtWWW3AUPSJM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiaomeng Tong , Will Deacon Subject: [PATCH 5.16 246/285] perf: qcom_l2_pmu: fix an incorrect NULL check on list iterator Date: Tue, 12 Apr 2022 08:31:43 +0200 Message-Id: <20220412062950.759803377@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220412062943.670770901@linuxfoundation.org> References: <20220412062943.670770901@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Xiaomeng Tong commit 2012a9e279013933885983cbe0a5fe828052563b upstream. The bug is here: return cluster; The list iterator value 'cluster' will *always* be set and non-NULL by list_for_each_entry(), so it is incorrect to assume that the iterator value will be NULL if the list is empty or no element is found. To fix the bug, return 'cluster' when found, otherwise return NULL. Cc: stable@vger.kernel.org Fixes: 21bdbb7102ed ("perf: add qcom l2 cache perf events driver") Signed-off-by: Xiaomeng Tong Link: https://lore.kernel.org/r/20220327055733.4070-1-xiam0nd.tong@gmail.com Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman --- drivers/perf/qcom_l2_pmu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/perf/qcom_l2_pmu.c +++ b/drivers/perf/qcom_l2_pmu.c @@ -736,7 +736,7 @@ static struct cluster_pmu *l2_cache_asso { u64 mpidr; int cpu_cluster_id; - struct cluster_pmu *cluster = NULL; + struct cluster_pmu *cluster; /* * This assumes that the cluster_id is in MPIDR[aff1] for @@ -758,10 +758,10 @@ static struct cluster_pmu *l2_cache_asso cluster->cluster_id); cpumask_set_cpu(cpu, &cluster->cluster_cpus); *per_cpu_ptr(l2cache_pmu->pmu_cluster, cpu) = cluster; - break; + return cluster; } - return cluster; + return NULL; } static int l2cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)