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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 44DC5C47082 for ; Tue, 1 Jun 2021 02:57:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 27A776135C for ; Tue, 1 Jun 2021 02:57:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232789AbhFAC6v (ORCPT ); Mon, 31 May 2021 22:58:51 -0400 Received: from szxga03-in.huawei.com ([45.249.212.189]:3361 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232516AbhFAC6q (ORCPT ); Mon, 31 May 2021 22:58:46 -0400 Received: from dggeme759-chm.china.huawei.com (unknown [172.30.72.54]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4FvGtl1579z65ll; Tue, 1 Jun 2021 10:53:19 +0800 (CST) Received: from localhost.localdomain (10.69.192.56) by dggeme759-chm.china.huawei.com (10.3.19.105) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Tue, 1 Jun 2021 10:57:02 +0800 From: Tian Tao To: , , , CC: Tian Tao , "Rafael J. Wysocki" Subject: [PATCH 2/2] drivers/base/node.c: use bin_attribute to avoid buff overflow Date: Tue, 1 Jun 2021 10:56:50 +0800 Message-ID: <1622516210-10886-3-git-send-email-tiantao6@hisilicon.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1622516210-10886-1-git-send-email-tiantao6@hisilicon.com> References: <1622516210-10886-1-git-send-email-tiantao6@hisilicon.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggeme759-chm.china.huawei.com (10.3.19.105) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Reading sys/devices/system/cpu/cpuX/nodeX/ returns cpumap and cpulist. However, the size of this file is limited to PAGE_SIZE because of the limitation for sysfs attribute. so we use bin_attribute instead of attribute to avoid NR_CPUS too big to cause buff overflow. Signed-off-by: Tian Tao Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" --- drivers/base/node.c | 49 +++++++++++++++++++++++++++++++------------------ 1 file changed, 31 insertions(+), 18 deletions(-) diff --git a/drivers/base/node.c b/drivers/base/node.c index f449dbb..a19be64 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -27,42 +27,42 @@ static struct bus_type node_subsys = { }; -static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf) +static ssize_t node_read_cpumap(struct kobject *kobj, bool list, + char *buf, loff_t off, size_t count) { ssize_t n; cpumask_var_t mask; + struct device *dev = kobj_to_dev(kobj); struct node *node_dev = to_node(dev); - /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */ - BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1)); - if (!alloc_cpumask_var(&mask, GFP_KERNEL)) return 0; cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask); - n = cpumap_print_to_pagebuf(list, buf, mask); + n = cpumap_print_to_buf(list, buf, mask, off, count); free_cpumask_var(mask); return n; } -static inline ssize_t cpumap_show(struct device *dev, - struct device_attribute *attr, - char *buf) +static inline ssize_t cpumap_read(struct file *file, struct kobject *kobj, + struct bin_attribute *attr, char *buf, + loff_t off, size_t count) { - return node_read_cpumap(dev, false, buf); + return node_read_cpumap(kobj, false, buf, off, count); } -static DEVICE_ATTR_RO(cpumap); -static inline ssize_t cpulist_show(struct device *dev, - struct device_attribute *attr, - char *buf) +static BIN_ATTR_RO(cpumap, 0); + +static inline ssize_t cpulist_read(struct file *file, struct kobject *kobj, + struct bin_attribute *attr, char *buf, + loff_t off, size_t count) { - return node_read_cpumap(dev, true, buf); + return node_read_cpumap(kobj, true, buf, off, count); } -static DEVICE_ATTR_RO(cpulist); +static BIN_ATTR_RO(cpulist, 0); /** * struct node_access_nodes - Access class device to hold user visible @@ -557,15 +557,28 @@ static ssize_t node_read_distance(struct device *dev, static DEVICE_ATTR(distance, 0444, node_read_distance, NULL); static struct attribute *node_dev_attrs[] = { - &dev_attr_cpumap.attr, - &dev_attr_cpulist.attr, &dev_attr_meminfo.attr, &dev_attr_numastat.attr, &dev_attr_distance.attr, &dev_attr_vmstat.attr, NULL }; -ATTRIBUTE_GROUPS(node_dev); + +static struct bin_attribute *node_dev_bin_attrs[] = { + &bin_attr_cpumap, + &bin_attr_cpulist, + NULL, +}; + +static const struct attribute_group node_dev_group = { + .attrs = node_dev_attrs, + .bin_attrs = node_dev_bin_attrs +}; + +static const struct attribute_group *node_dev_groups[] = { + &node_dev_group, + NULL, +}; #ifdef CONFIG_HUGETLBFS /* -- 2.7.4