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 9F3ABC606CF for ; Mon, 8 Jul 2019 23:42:57 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2757720693 for ; Mon, 8 Jul 2019 23:42:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2757720693 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zte.com.cn Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 45jMSt0VkQzDqSm for ; Tue, 9 Jul 2019 09:42:54 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=zte.com.cn (client-ip=63.217.80.70; helo=mxhk.zte.com.cn; envelope-from=wen.yang99@zte.com.cn; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=zte.com.cn Received: from mxhk.zte.com.cn (mxhk.zte.com.cn [63.217.80.70]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 45jMQx0sWyzDqFD for ; Tue, 9 Jul 2019 09:41:10 +1000 (AEST) Received: from mse-fl1.zte.com.cn (unknown [10.30.14.238]) by Forcepoint Email with ESMTPS id C0D3B9A00443B12BF253; Tue, 9 Jul 2019 07:41:06 +0800 (CST) Received: from notes_smtp.zte.com.cn ([10.30.1.239]) by mse-fl1.zte.com.cn with ESMTP id x68NerpI077801; Tue, 9 Jul 2019 07:40:53 +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 2019070907410350-2182061 ; Tue, 9 Jul 2019 07:41:03 +0800 From: Wen Yang To: linux-kernel@vger.kernel.org Subject: [PATCH v4] cpufreq/pasemi: fix an use-after-free in pas_cpufreq_cpu_init() Date: Tue, 9 Jul 2019 07:39:04 +0800 Message-Id: <1562629144-13584-1-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 2019-07-09 07:41:03, Serialize by Router on notes_smtp/zte_ltd(Release 9.0.1FP7|August 17, 2016) at 2019-07-09 07:40:56, Serialize complete at 2019-07-09 07:40:56 X-MAIL: mse-fl1.zte.com.cn x68NerpI077801 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: wang.yi59@zte.com.cn, linux-pm@vger.kernel.org, Viresh Kumar , "Rafael J. Wysocki" , xue.zhihong@zte.com.cn, cheng.shengyu@zte.com.cn, linuxppc-dev@lists.ozlabs.org, Wen Yang Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" 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 --- v4: restore the blank line. v3: fix a leaked reference. v2: clean up the code according to the advice of viresh. drivers/cpufreq/pasemi-cpufreq.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/pasemi-cpufreq.c b/drivers/cpufreq/pasemi-cpufreq.c index 6b1e4ab..f0c98fc 100644 --- a/drivers/cpufreq/pasemi-cpufreq.c +++ b/drivers/cpufreq/pasemi-cpufreq.c @@ -128,20 +128,21 @@ 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 +197,7 @@ 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 +206,7 @@ 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