From patchwork Thu Oct 27 09:19:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yingliang X-Patchwork-Id: 13021842 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31346C38A2D for ; Thu, 27 Oct 2022 09:20:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235427AbiJ0JUa (ORCPT ); Thu, 27 Oct 2022 05:20:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40008 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235298AbiJ0JUW (ORCPT ); Thu, 27 Oct 2022 05:20:22 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 415582228C; Thu, 27 Oct 2022 02:20:13 -0700 (PDT) Received: from dggpemm500022.china.huawei.com (unknown [172.30.72.55]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4Myg7816n6zJnDr; Thu, 27 Oct 2022 17:17:24 +0800 (CST) Received: from dggpemm500007.china.huawei.com (7.185.36.183) by dggpemm500022.china.huawei.com (7.185.36.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 27 Oct 2022 17:20:11 +0800 Received: from huawei.com (10.175.103.91) by dggpemm500007.china.huawei.com (7.185.36.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 27 Oct 2022 17:20:11 +0800 From: Yang Yingliang To: , CC: , , , , Subject: [PATCH] rbd: fix possible memory leak in rbd_sysfs_init() Date: Thu, 27 Oct 2022 17:19:18 +0800 Message-ID: <20221027091918.2294132-1-yangyingliang@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.175.103.91] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm500007.china.huawei.com (7.185.36.183) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org If device_register() returns error in rbd_sysfs_init(), name of kobject which is allocated in dev_set_name() called in device_add() is leaked. As comment of device_add() says, it should call put_device() to drop the reference count that was set in device_initialize() when it fails, so the name can be freed in kobject_cleanup(). Fault injection test can trigger this problem: unreferenced object 0xffff88810173aa78 (size 8): comm "modprobe", pid 247, jiffies 4294714278 (age 31.789s) hex dump (first 8 bytes): 72 62 64 00 81 88 ff ff rbd..... backtrace: [<00000000f58fae56>] __kmalloc_node_track_caller+0x44/0x1b0 [<00000000bdd44fe7>] kstrdup+0x3a/0x70 [<00000000f7844d0b>] kstrdup_const+0x63/0x80 [<000000001b0a0eeb>] kvasprintf_const+0x10b/0x190 [<00000000a47bd894>] kobject_set_name_vargs+0x56/0x150 [<00000000d5edbf18>] dev_set_name+0xab/0xe0 [<00000000f5153e80>] device_add+0x106/0x1f20 Fixes: dfc5606dc513 ("rbd: replace the rbd sysfs interface") Signed-off-by: Yang Yingliang Reviewed-by: Alex Elder --- drivers/block/rbd.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index f9e39301c4af..04453f4a319c 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -7222,8 +7222,10 @@ static int __init rbd_sysfs_init(void) int ret; ret = device_register(&rbd_root_dev); - if (ret < 0) + if (ret < 0) { + put_device(&rbd_root_dev); return ret; + } ret = bus_register(&rbd_bus_type); if (ret < 0)