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=unavailable 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 A568DC5B57D for ; Mon, 8 Jul 2019 08:52:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8977B2084A for ; Mon, 8 Jul 2019 08:52:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729073AbfGHIwC (ORCPT ); Mon, 8 Jul 2019 04:52:02 -0400 Received: from mx7.zte.com.cn ([202.103.147.169]:36526 "EHLO mxct.zte.com.cn" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728884AbfGHIwC (ORCPT ); Mon, 8 Jul 2019 04:52:02 -0400 Received: from mse-fl2.zte.com.cn (unknown [10.30.14.239]) by Forcepoint Email with ESMTPS id D496EBE0043BE622BB03; Mon, 8 Jul 2019 16:51:58 +0800 (CST) Received: from notes_smtp.zte.com.cn ([10.30.1.239]) by mse-fl2.zte.com.cn with ESMTP id x688oVnj044240; Mon, 8 Jul 2019 16:50:31 +0800 (GMT-8) (envelope-from wen.yang99@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 2019070816503612-2168893 ; Mon, 8 Jul 2019 16:50:36 +0800 From: Wen Yang To: linux-kernel@vger.kernel.org Cc: xue.zhihong@zte.com.cn, wang.yi59@zte.com.cn, cheng.shengyu@zte.com.cn, Wen Yang , "Rafael J. Wysocki" , Viresh Kumar , linuxppc-dev@lists.ozlabs.org, linux-pm@vger.kernel.org Subject: [PATCH v3] cpufreq/pasemi: fix an use-after-free in pas_cpufreq_cpu_init() Date: Mon, 8 Jul 2019 16:48:46 +0800 Message-Id: <1562575726-17438-1-git-send-email-wen.yang99@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 2019-07-08 16:50:36, Serialize by Router on notes_smtp/zte_ltd(Release 9.0.1FP7|August 17, 2016) at 2019-07-08 16:50:33, Serialize complete at 2019-07-08 16:50:33 X-MAIL: mse-fl2.zte.com.cn x688oVnj044240 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The cpu variable is still being used in the of_get_property() call after the of_node_put() call, which may result in use-after-free. Fixes: a9acc26b75f ("cpufreq/pasemi: fix possible object reference leak") Signed-off-by: Wen Yang Cc: "Rafael J. Wysocki" Cc: Viresh Kumar Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- v3: fix a leaked reference. v2: clean up the code according to the advice of viresh. drivers/cpufreq/pasemi-cpufreq.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/cpufreq/pasemi-cpufreq.c b/drivers/cpufreq/pasemi-cpufreq.c index 6b1e4ab..9dc5163 100644 --- a/drivers/cpufreq/pasemi-cpufreq.c +++ b/drivers/cpufreq/pasemi-cpufreq.c @@ -128,20 +128,20 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) int cur_astate, idx; struct resource res; struct device_node *cpu, *dn; - int err = -ENODEV; + int err; cpu = of_get_cpu_node(policy->cpu, NULL); - - of_node_put(cpu); if (!cpu) - goto out; + return -ENODEV; dn = of_find_compatible_node(NULL, NULL, "1682m-sdc"); if (!dn) dn = of_find_compatible_node(NULL, NULL, "pasemi,pwrficient-sdc"); - if (!dn) + if (!dn) { + err = -ENODEV; goto out; + } err = of_address_to_resource(dn, 0, &res); of_node_put(dn); if (err) @@ -196,6 +196,7 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) policy->cur = pas_freqs[cur_astate].frequency; ppc_proc_freq = policy->cur * 1000ul; + of_node_put(cpu); return cpufreq_generic_init(policy, pas_freqs, get_gizmo_latency()); out_unmap_sdcpwr: @@ -204,6 +205,7 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) out_unmap_sdcasr: iounmap(sdcasr_mapbase); out: + of_node_put(cpu); return err; } -- 2.9.5