From patchwork Wed Nov 6 01:12:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jinjie Ruan X-Patchwork-Id: 841645 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DF7F017E015; Wed, 6 Nov 2024 01:13:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.255 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730855591; cv=none; b=jRx7f00PUO1uz6aUrqk2aMiDBfKc45fWJ8eBPYEzZwjypAQ1U4iKSHU7JJqaf6RbCMEXH5OvsViaDNIwGfecc1AoajEAFUnu9owteSPoEo0FMPLg6/q0xYPGOQmliL9qGTmDu/E0r5MmOVMH6HtZoMhhBlQyG+qsfTi4P7VLdKk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730855591; c=relaxed/simple; bh=ikL5huFq2NOcJ6EBTw42nabn5i/Xih/2D+cLnu6GtcU=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=QcuZkHDPS3No6ll/ZvCFz31yH83vVXjPJX70c3+kH7eIJhsBmJuSZR67RgHzJV9t6H0L9s2XbCiukFg2/smQzENxAMuhBvKsbEPBu3caVLUZru8SrIigP/9LK91S3lMVHQqeq6OGEjXN/tnPVm3ztUpSvF0Oje84Vg5wXAKcSYM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.255 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.105]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4XjnFd2ds4z1T7vQ; Wed, 6 Nov 2024 09:10:45 +0800 (CST) Received: from kwepemg200008.china.huawei.com (unknown [7.202.181.35]) by mail.maildlp.com (Postfix) with ESMTPS id C869D140155; Wed, 6 Nov 2024 09:13:04 +0800 (CST) Received: from huawei.com (10.90.53.73) by kwepemg200008.china.huawei.com (7.202.181.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Wed, 6 Nov 2024 09:13:04 +0800 From: Jinjie Ruan To: , , , CC: , Subject: [PATCH -next] cpufreq: CPPC: Fix wrong return value in cppc_get_cpu_cost() Date: Wed, 6 Nov 2024 09:12:38 +0800 Message-ID: <20241106011238.2407104-1-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemg200008.china.huawei.com (7.202.181.35) cppc_get_cpu_cost() return 0 if the policy is NULL. Then in em_compute_costs(), the later zero check for cost is not valid as cost is uninitialized. As Quentin pointed out, kernel energy model core check the return value of get_cost() first, so if the callback failed it should tell the core. Return -EINVAL to fix it. Fixes: 1a1374bb8c59 ("cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()") Reported-by: Dan Carpenter Closes: https://lore.kernel.org/all/c4765377-7830-44c2-84fa-706b6e304e10@stanley.mountain/ Signed-off-by: Jinjie Ruan Suggested-by: Quentin Perret --- drivers/cpufreq/cppc_cpufreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index aa5dd194fc5b..cdc569cf7743 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -475,7 +475,7 @@ static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz, policy = cpufreq_cpu_get_raw(cpu_dev->id); if (!policy) - return 0; + return -EINVAL; cpu_data = policy->driver_data; perf_caps = &cpu_data->perf_caps;