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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9DCB3C54EE9 for ; Sun, 25 Sep 2022 17:40:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 04F868E0020; Sun, 25 Sep 2022 13:40:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F41F88E0007; Sun, 25 Sep 2022 13:40:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E09248E0020; Sun, 25 Sep 2022 13:40:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id CDCFC8E0007 for ; Sun, 25 Sep 2022 13:40:17 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 9EA95C0255 for ; Sun, 25 Sep 2022 17:40:17 +0000 (UTC) X-FDA: 79951321674.23.1E91B29 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf15.hostedemail.com (Postfix) with ESMTP id 4B55EA0005 for ; Sun, 25 Sep 2022 17:40:17 +0000 (UTC) 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 84D5360EBB; Sun, 25 Sep 2022 17:40:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 758AAC433D6; Sun, 25 Sep 2022 17:40:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1664127615; bh=J6MQ6nba3bNXWm13BqriajL0itO1C/a8zLexNF1ZFAg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OkZq0jGhSkSPq3kPxaEBOl3PECjK2uwJU8qNaC8mEG878Nx9bpO9VH5hWpcNPtZSM 8NkHoT0XQOvB4qzY8nquutwdwOjgFIRjYGnhQmnThHYNzyn7xnyZlpBz9Be3dlB8jJ aCVo56CPytTSyD0RHmHgIqlMJGLJNU1UztPfbPryWs2LTKPjdrWK6Shf60MQQ0FOm0 paZ/GxPMeJ/Wt88zj70ZPOy5lDnNGtQBgILNuD8+YoBwTTDXWaGF+KnGeHSr7w5Cgx zZenW1YI/ihUwvNBJnzJrxDCKmGiZT9X4gE/Ddyea4ESq27QxhCHD+HiYdvMGA6aoC Uj7oCUZWPniMQ== From: SeongJae Park To: Levi Yun Cc: sj@kernel.org, akpm@linux-foundation.org, damon@lists.linux.dev, linux-mm@kvack.org Subject: Re: [PATCH] damon/sysfs: Fix possible memleak on damon_sysfs_add_target. Date: Sun, 25 Sep 2022 17:40:13 +0000 Message-Id: <20220925174013.59565-1-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220925140257.23431-1-ppbuk5246@gmail.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1664127617; a=rsa-sha256; cv=none; b=T7tB4FtCz+FR4z8SlPoxB02NA52890qDqV/aBWanycQvBj1ul+dcmjw9lRyJPTrlahA6Qc fuTMZF6u26dTF47w5YSU1TiQ9q1oajmYhvC6bQBZDqRe+r7T80uIUJHKVxZR6U8FTILYLU WZ3VBL8qUkf+Mg3e0gK9wZlRnjXRpIE= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=OkZq0jGh; spf=pass (imf15.hostedemail.com: domain of sj@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=sj@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1664127617; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Sx0e4uaPREw41UqE/Kz9ZXpopu9viQp47Rkk7YAOmkw=; b=dUS2JfO0/sX0kC132ffof2ShtQhXSKvInHK7NMRs1H8dNya+v+sCQJJaoA0IU3yQGdsupX Wjm8VbAtnpAiRIgeUel6QxyPja3w3BWWD4xcP1mN0VX88BRhpA11iWHiHbrzQOWnDlYGoo 4fPaCacp1k0csgxj6sNo7TeTf5uxWAU= X-Rspamd-Queue-Id: 4B55EA0005 X-Rspamd-Server: rspam07 X-Rspam-User: Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=OkZq0jGh; spf=pass (imf15.hostedemail.com: domain of sj@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=sj@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-Stat-Signature: te96a3qrtfb9q4b14xr36od7ac3demau X-HE-Tag: 1664127617-719853 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, 25 Sep 2022 23:02:57 +0900 Levi Yun wrote: > When damon_sysfs_add_target couldn't find proper task, > New allocated damon_target structure isn't registered yet, > So, it's impossible to free new allocated one by > damon_sysfs_destroy_targets. Good finding, thanks! > > By calling additional damon_free_target when find_get_pid function, > Fix possible memory leak. > > Signed-off-by: Levi Yun Could we add relevant 'Fixes: ' and 'Cc: ' tags? > --- > mm/damon/sysfs.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c > index 7488e27c87c3..28ed07d26d55 100644 > --- a/mm/damon/sysfs.c > +++ b/mm/damon/sysfs.c > @@ -2184,8 +2184,11 @@ static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target, > return -ENOMEM; > if (damon_target_has_pid(ctx)) { > t->pid = find_get_pid(sys_target->pid); > - if (!t->pid) > + if (!t->pid) { > + damon_free_target(t); > + Seems unnecessary new line? > goto destroy_targets_out; > + } > } Looks good to me, but... How about simply doing 'damon_add_target()' before 'if (damon_target_has_pid())', like below? ``` diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 455215a5c059..9f1219a67e3f 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -2172,12 +2172,12 @@ static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target, if (!t) return -ENOMEM; + damon_add_target(ctx, t); if (damon_target_has_pid(ctx)) { t->pid = find_get_pid(sys_target->pid); if (!t->pid) goto destroy_targets_out; } - damon_add_target(ctx, t); err = damon_sysfs_set_regions(t, sys_target->regions); if (err) goto destroy_targets_out; ``` Thanks, SJ > damon_add_target(ctx, t); > err = damon_sysfs_set_regions(t, sys_target->regions); > -- > 2.35.1 > >