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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 038A7C433FE for ; Mon, 3 Oct 2022 07:18:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230110AbiJCHSR (ORCPT ); Mon, 3 Oct 2022 03:18:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48052 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229949AbiJCHRJ (ORCPT ); Mon, 3 Oct 2022 03:17:09 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB7A546872; Mon, 3 Oct 2022 00:14:05 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3C3A1B80E69; Mon, 3 Oct 2022 07:14:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A945EC433D6; Mon, 3 Oct 2022 07:14:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1664781243; bh=+Rg7jiz/BdLa2YuHZAziCH9S3XwBEVJjdLlinQYrA/k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lijNi25JxUHd3a1WO4yOo+JlgdiG9ZQkdbcfiybQyvs3m8eiN/CCjP5sBwGRm2UPj J1AHrbhpUAyrHg3tsO/Tyd0sS2XU01VSqFbQ2TBRCW1OBMwBPyj+RbnlmidTjWlu4s 41oOp2tm2ZR2/zexgzbawsz0ZXL0AV1027PRslwI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, SeongJae Park , Andrew Morton Subject: [PATCH 5.19 022/101] mm/damon/dbgfs: fix memory leak when using debugfs_lookup() Date: Mon, 3 Oct 2022 09:10:18 +0200 Message-Id: <20221003070725.042551819@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221003070724.490989164@linuxfoundation.org> References: <20221003070724.490989164@linuxfoundation.org> User-Agent: quilt/0.67 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: Greg Kroah-Hartman commit 1552fd3ef7dbe07208b8ae84a0a6566adf7dfc9d upstream. When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. Fix this up by properly calling dput(). Link: https://lkml.kernel.org/r/20220902191149.112434-1-sj@kernel.org Fixes: 75c1c2b53c78b ("mm/damon/dbgfs: support multiple contexts") Signed-off-by: Greg Kroah-Hartman Signed-off-by: SeongJae Park Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- mm/damon/dbgfs.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -853,6 +853,7 @@ static int dbgfs_rm_context(char *name) struct dentry *root, *dir, **new_dirs; struct damon_ctx **new_ctxs; int i, j; + int ret = 0; if (damon_nr_running_ctxs()) return -EBUSY; @@ -867,14 +868,16 @@ static int dbgfs_rm_context(char *name) new_dirs = kmalloc_array(dbgfs_nr_ctxs - 1, sizeof(*dbgfs_dirs), GFP_KERNEL); - if (!new_dirs) - return -ENOMEM; + if (!new_dirs) { + ret = -ENOMEM; + goto out_dput; + } new_ctxs = kmalloc_array(dbgfs_nr_ctxs - 1, sizeof(*dbgfs_ctxs), GFP_KERNEL); if (!new_ctxs) { - kfree(new_dirs); - return -ENOMEM; + ret = -ENOMEM; + goto out_new_dirs; } for (i = 0, j = 0; i < dbgfs_nr_ctxs; i++) { @@ -894,7 +897,13 @@ static int dbgfs_rm_context(char *name) dbgfs_ctxs = new_ctxs; dbgfs_nr_ctxs--; - return 0; + goto out_dput; + +out_new_dirs: + kfree(new_dirs); +out_dput: + dput(dir); + return ret; } static ssize_t dbgfs_rm_context_write(struct file *file,