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 470B6C4167B for ; Thu, 14 Apr 2022 15:20:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356653AbiDNPTc (ORCPT ); Thu, 14 Apr 2022 11:19:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47178 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347680AbiDNN70 (ORCPT ); Thu, 14 Apr 2022 09:59:26 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A20E49C81; Thu, 14 Apr 2022 06:51:14 -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 E874BB8298C; Thu, 14 Apr 2022 13:51:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 34054C385A1; Thu, 14 Apr 2022 13:51:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649944271; bh=wK2YngWWIWxMomu3G/G3fja+4rlWu+67C42w0ivXxVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mQW4q04Vu17W64H6Vbx1TXZ4P6CZ0vX3U5a20ljAWC7AgbNxGhhUAKT0G8tLUZlT0 Ru/ab1fZwYTZcEZnKCYyuZzXenlRzb61vXR8Ku+kBxfQxmczGmY4EM4BJmnLv19Ufl d17a1YuIyiGz9/l5D9z+LWAgS1ccIA569NRyiVxo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiaomeng Tong , Will Deacon Subject: [PATCH 5.4 455/475] perf: qcom_l2_pmu: fix an incorrect NULL check on list iterator Date: Thu, 14 Apr 2022 15:14:00 +0200 Message-Id: <20220414110907.791052190@linuxfoundation.org> X-Mailer: git-send-email 2.35.2 In-Reply-To: <20220414110855.141582785@linuxfoundation.org> References: <20220414110855.141582785@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: linux-kernel@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 @@ -781,7 +781,7 @@ 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 @@ -803,10 +803,10 @@ 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)