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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 CE0E4C43600 for ; Mon, 10 May 2021 11:11:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9B0CC61480 for ; Mon, 10 May 2021 11:11:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233964AbhEJLM2 (ORCPT ); Mon, 10 May 2021 07:12:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:41711 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233538AbhEJKuM (ORCPT ); Mon, 10 May 2021 06:50:12 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1488B619F1; Mon, 10 May 2021 10:39:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620643165; bh=K7MP6scl/OWuLlk6iKFJzWTsh7jEaPUuIVAJPFVdBtQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WGY0dfyR49fq6YdAWXhccUYgggPHpHYUCtvJTqS+UL3kGvvFPgvJcehkD5aSLKTxt xvrybnFvTRlJGaOt/g4OTT+IraSWUvWpBDIXQ64Q0Pc64frYiw90WaDKzAFJo8IHHL 017jD8xy4uX8cOUDJ0QvJ85JUTMAeaGIXAtNZWTY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gioh Kim , Jack Wang , Jens Axboe , Sasha Levin Subject: [PATCH 5.10 205/299] block/rnbd-clt: Fix missing a memory free when unloading the module Date: Mon, 10 May 2021 12:20:02 +0200 Message-Id: <20210510102011.717028766@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102004.821838356@linuxfoundation.org> References: <20210510102004.821838356@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Gioh Kim [ Upstream commit 12b06533104e802df73c1fbe159437c19933d6c0 ] When unloading the rnbd-clt module, it does not free a memory including the filename of the symbolic link to /sys/block/rnbdX. It is found by kmemleak as below. unreferenced object 0xffff9f1a83d3c740 (size 16): comm "bash", pid 736, jiffies 4295179665 (age 9841.310s) hex dump (first 16 bytes): 21 64 65 76 21 6e 75 6c 6c 62 30 40 62 6c 61 00 !dev!nullb0@bla. backtrace: [<0000000039f0c55e>] 0xffffffffc0456c24 [<000000001aab9513>] kernfs_fop_write+0xcf/0x1c0 [<00000000db5aa4b3>] vfs_write+0xdb/0x1d0 [<000000007a2e2207>] ksys_write+0x65/0xe0 [<00000000055e280a>] do_syscall_64+0x50/0x1b0 [<00000000c2b51831>] entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: Gioh Kim Signed-off-by: Jack Wang Link: https://lore.kernel.org/r/20210419073722.15351-13-gi-oh.kim@ionos.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/block/rnbd/rnbd-clt-sysfs.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c index d9dd138ca9c6..5613cd45866b 100644 --- a/drivers/block/rnbd/rnbd-clt-sysfs.c +++ b/drivers/block/rnbd/rnbd-clt-sysfs.c @@ -433,10 +433,14 @@ void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev) * i.e. rnbd_clt_unmap_dev_store() leading to a sysfs warning because * of sysfs link already was removed already. */ - if (dev->blk_symlink_name && try_module_get(THIS_MODULE)) { - sysfs_remove_link(rnbd_devs_kobj, dev->blk_symlink_name); + if (dev->blk_symlink_name) { + if (try_module_get(THIS_MODULE)) { + sysfs_remove_link(rnbd_devs_kobj, dev->blk_symlink_name); + module_put(THIS_MODULE); + } + /* It should be freed always. */ kfree(dev->blk_symlink_name); - module_put(THIS_MODULE); + dev->blk_symlink_name = NULL; } } -- 2.30.2