From nobody Mon Apr 6 19:56:43 2026 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 47EEEC6FA82 for ; Fri, 2 Sep 2022 19:12:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229646AbiIBTMN (ORCPT ); Fri, 2 Sep 2022 15:12:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48116 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229751AbiIBTMJ (ORCPT ); Fri, 2 Sep 2022 15:12:09 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2FA6FBA4D; Fri, 2 Sep 2022 12:12:04 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 50EED6229E; Fri, 2 Sep 2022 19:12:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1BDE9C433D6; Fri, 2 Sep 2022 19:12:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1662145923; bh=rJDLXs4RxM5/uTreWGTpem458YPycLhkzqUiqONrjDY=; h=From:To:Cc:Subject:Date:From; b=aBZGi0RYXJahnjFCnOvAslff2adgx6/RpvP1D3sAHZhvIh2wnbv8h31jmgElsGIkW oBAGnyCCnF4EOlcsW1lqqVCUwFB7h5NiSJwfU9Dmi7d3wDLEjo2RNpSsXxOIzLGDeg SwD3jk1ueOHubNqwACGDGfCADYqtCIELrC2Ec9h8pr9K0M11otV6lL3Klu5njJ8Gk5 KC4RS86RroeG/sVkFwv1EHBP3Zf1iYX6vcAWp7sBARNc6aq7VFCpTkb4UCxYfMbqDN yOKwMMHl4qM42NW79eShU+czoiEfdsRVXa4VAhP7GAmaV98Ao+sxQAUAUsSeYwAIHE BDTPqYtALPA0Q== From: SeongJae Park To: akpm@linux-foundation.org Cc: sj@kernel.org, gregkh@linuxfoundation.org, damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH v2] mm/damon/dbgfs: fix memory leak when using Date: Fri, 2 Sep 2022 19:11:49 +0000 Message-Id: <20220902191149.112434-1-sj@kernel.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Greg Kroah-Hartman debugfs_lookup() Date: Fri, 2 Sep 2022 14:56:31 +0200 [thread overview] Message-ID: <20220902125631.128329-1-gregkh@linuxfoundation.org> (raw) 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(). Fixes: 75c1c2b53c78b ("mm/damon/dbgfs: support multiple contexts") Cc: # 5.15.x Cc: SeongJae Park Cc: Andrew Morton Cc: damon@lists.linux.dev Cc: linux-mm@kvack.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Andrew Morton Signed-off-by: SeongJae Park --- Changes from v1 (https://lore.kernel.org/damon/20220902125631.128329-1-gregkh@linuxfoundati= on.org/) - Call dput() for failure-return case (Andrew Morton) mm/damon/dbgfs.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 3b55a1b219b5..652a94deafe3 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -884,6 +884,7 @@ static int dbgfs_rm_context(char *name) struct dentry *root, *dir, **new_dirs; struct damon_ctx **new_ctxs; int i, j; + int ret =3D 0; =20 if (damon_nr_running_ctxs()) return -EBUSY; @@ -898,14 +899,16 @@ static int dbgfs_rm_context(char *name) =20 new_dirs =3D kmalloc_array(dbgfs_nr_ctxs - 1, sizeof(*dbgfs_dirs), GFP_KERNEL); - if (!new_dirs) - return -ENOMEM; + if (!new_dirs) { + ret =3D -ENOMEM; + goto out_dput; + } =20 new_ctxs =3D kmalloc_array(dbgfs_nr_ctxs - 1, sizeof(*dbgfs_ctxs), GFP_KERNEL); if (!new_ctxs) { - kfree(new_dirs); - return -ENOMEM; + ret =3D -ENOMEM; + goto out_new_dirs; } =20 for (i =3D 0, j =3D 0; i < dbgfs_nr_ctxs; i++) { @@ -925,7 +928,13 @@ static int dbgfs_rm_context(char *name) dbgfs_ctxs =3D new_ctxs; dbgfs_nr_ctxs--; =20 - return 0; + goto out_dput; + +out_new_dirs: + kfree(new_dirs); +out_dput: + dput(dir); + return ret; } =20 static ssize_t dbgfs_rm_context_write(struct file *file, --=20 2.25.1