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=-9.7 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 DAC39C76186 for ; Wed, 17 Jul 2019 03:59:20 +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 3587120818 for ; Wed, 17 Jul 2019 03:59:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3587120818 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 45pNn156MFzDqSx for ; Wed, 17 Jul 2019 13:59:17 +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 45pNlB4VkGzDqC0 for ; Wed, 17 Jul 2019 13:57:39 +1000 (AEST) Received: from mse-fl1.zte.com.cn (unknown [10.30.14.238]) by Forcepoint Email with ESMTPS id 5AE79B2E9F7A54F96F16; Wed, 17 Jul 2019 11:57:35 +0800 (CST) Received: from notes_smtp.zte.com.cn ([10.30.1.239]) by mse-fl1.zte.com.cn with ESMTP id x6H3vDmB027532; Wed, 17 Jul 2019 11:57:13 +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 2019071711572903-2389314 ; Wed, 17 Jul 2019 11:57:29 +0800 From: Wen Yang To: rjw@rjwysocki.net Subject: [PATCH v7] cpufreq/pasemi: fix an use-after-free in pas_cpufreq_cpu_init() Date: Wed, 17 Jul 2019 11:55:04 +0800 Message-Id: <1563335704-25562-1-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 2019-07-17 11:57:29, Serialize by Router on notes_smtp/zte_ltd(Release 9.0.1FP7|August 17, 2016) at 2019-07-17 11:57:16, Serialize complete at 2019-07-17 11:57:16 X-MAIL: mse-fl1.zte.com.cn x6H3vDmB027532 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@linaro.org, linux-kernel@vger.kernel.org, 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: a9acc26b75f6 ("cpufreq/pasemi: fix possible object reference leak") Signed-off-by: Wen Yang Cc: "Rafael J. Wysocki" Cc: Viresh Kumar Cc: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- v7: adapt to commit ("cpufreq: Make cpufreq_generic_init() return void") v6: keep the blank line and fix warning: label 'out_unmap_sdcpwr' defined but not used. v5: put together the code to get, use, and release cpu device_node. 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 | 23 +++++++++-------------- 1 file changed, 9 insertions(+), 14 deletions(-) diff --git a/drivers/cpufreq/pasemi-cpufreq.c b/drivers/cpufreq/pasemi-cpufreq.c index 93f39a1..c66f566 100644 --- a/drivers/cpufreq/pasemi-cpufreq.c +++ b/drivers/cpufreq/pasemi-cpufreq.c @@ -131,10 +131,18 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) int err = -ENODEV; cpu = of_get_cpu_node(policy->cpu, NULL); + if (!cpu) + goto out; + max_freqp = of_get_property(cpu, "clock-frequency", NULL); of_node_put(cpu); - if (!cpu) + if (!max_freqp) { + err = -EINVAL; goto out; + } + + /* we need the freq in kHz */ + max_freq = *max_freqp / 1000; dn = of_find_compatible_node(NULL, NULL, "1682m-sdc"); if (!dn) @@ -171,16 +179,6 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) } pr_debug("init cpufreq on CPU %d\n", policy->cpu); - - max_freqp = of_get_property(cpu, "clock-frequency", NULL); - if (!max_freqp) { - err = -EINVAL; - goto out_unmap_sdcpwr; - } - - /* we need the freq in kHz */ - max_freq = *max_freqp / 1000; - pr_debug("max clock-frequency is at %u kHz\n", max_freq); pr_debug("initializing frequency table\n"); @@ -199,9 +197,6 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) cpufreq_generic_init(policy, pas_freqs, get_gizmo_latency()); return 0; -out_unmap_sdcpwr: - iounmap(sdcpwr_mapbase); - out_unmap_sdcasr: iounmap(sdcasr_mapbase); out: -- 2.9.5