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=-7.6 required=3.0 tests=DATE_IN_PAST_06_12, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 C0378C31E44 for ; Wed, 12 Jun 2019 01:27:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A1ABB20866 for ; Wed, 12 Jun 2019 01:27:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406807AbfFLB1k (ORCPT ); Tue, 11 Jun 2019 21:27:40 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:18130 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2406215AbfFLB1k (ORCPT ); Tue, 11 Jun 2019 21:27:40 -0400 Received: from DGGEMS409-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 7885718CA3B9CC4C27AE; Wed, 12 Jun 2019 09:27:38 +0800 (CST) Received: from localhost (10.133.213.239) by DGGEMS409-HUB.china.huawei.com (10.3.19.209) with Microsoft SMTP Server id 14.3.439.0; Wed, 12 Jun 2019 09:27:28 +0800 From: YueHaibing To: , , CC: , YueHaibing Subject: [PATCH v4] kernel/module: Fix mem leak in module_add_modinfo_attrs Date: Tue, 11 Jun 2019 23:00:07 +0800 Message-ID: <20190611150007.21064-1-yuehaibing@huawei.com> X-Mailer: git-send-email 2.10.2.windows.1 In-Reply-To: <20190603144554.18168-1-yuehaibing@huawei.com> References: <20190603144554.18168-1-yuehaibing@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.133.213.239] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In module_add_modinfo_attrs if sysfs_create_file fails, we forget to free allocated modinfo_attrs and roll back the sysfs files. Fixes: 03e88ae1b13d ("[PATCH] fix module sysfs files reference counting") Signed-off-by: YueHaibing --- v4: call module_remove_modinfo_attrs only while i > 0 v3: reuse module_remove_modinfo_attrs v2: free from '--i' instead of 'i--' --- kernel/module.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index f954d72..3310a39 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1696,6 +1696,8 @@ static int add_usage_links(struct module *mod) return ret; } +static void module_remove_modinfo_attrs(struct module *mod, int end); + static int module_add_modinfo_attrs(struct module *mod) { struct module_attribute *attr; @@ -1710,24 +1712,34 @@ static int module_add_modinfo_attrs(struct module *mod) return -ENOMEM; temp_attr = mod->modinfo_attrs; - for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { + for (i = 0; (attr = modinfo_attrs[i]); i++) { if (!attr->test || attr->test(mod)) { memcpy(temp_attr, attr, sizeof(*temp_attr)); sysfs_attr_init(&temp_attr->attr); error = sysfs_create_file(&mod->mkobj.kobj, &temp_attr->attr); + if (error) + goto error_out; ++temp_attr; } } + + return 0; + +error_out: + if (i > 0) + module_remove_modinfo_attrs(mod, --i); return error; } -static void module_remove_modinfo_attrs(struct module *mod) +static void module_remove_modinfo_attrs(struct module *mod, int end) { struct module_attribute *attr; int i; for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { + if (end >= 0 && i > end) + break; /* pick a field to test for end of list */ if (!attr->attr.name) break; @@ -1815,7 +1827,7 @@ static int mod_sysfs_setup(struct module *mod, return 0; out_unreg_modinfo_attrs: - module_remove_modinfo_attrs(mod); + module_remove_modinfo_attrs(mod, -1); out_unreg_param: module_param_sysfs_remove(mod); out_unreg_holders: @@ -1851,7 +1863,7 @@ static void mod_sysfs_fini(struct module *mod) { } -static void module_remove_modinfo_attrs(struct module *mod) +static void module_remove_modinfo_attrs(struct module *mod, int end) { } @@ -1867,7 +1879,7 @@ static void init_param_lock(struct module *mod) static void mod_sysfs_teardown(struct module *mod) { del_usage_links(mod); - module_remove_modinfo_attrs(mod); + module_remove_modinfo_attrs(mod, -1); module_param_sysfs_remove(mod); kobject_put(mod->mkobj.drivers_dir); kobject_put(mod->holders_dir); -- 2.7.4