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,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 604B4C433F5 for ; Mon, 13 Sep 2021 22:38:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 479F361163 for ; Mon, 13 Sep 2021 22:38:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343529AbhIMWkN (ORCPT ); Mon, 13 Sep 2021 18:40:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:51068 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348673AbhIMWhK (ORCPT ); Mon, 13 Sep 2021 18:37:10 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 38B5B61283; Mon, 13 Sep 2021 22:35:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631572516; bh=cTg0XQYisPWumgunZBEDqjWz7SV7k3sH8/WB6KzyuQU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=blpkHv+d6OVtCmZBCEj7eVURnhzcERDyYQet10UFiCDBU//UuJlmMOdaxHUHpef/s fUU6xtymLR11e3HVynRH3aObJYZwlznqpTe202Dkqo0myxeSBh6baU0LEVLn+xK1RY CMNOwnpN6707HLl1S3pt52ggu025RGBM/jgMtYGLdh2Pu0av6lGVHeuRjsWEsc5Hu/ jIU3Dz6bvLgzUxmZAE2G8EgtMwg3IQOILQ9vsE/d+RXR75cgl5v0G5LMRTeqnE5zi5 HvITtdtJEs1MxMDQfhbG8fdyU+CAOnyl0KhTO1Bkkk6AMMN1ZTG1vDwznLm/D53rfc 587crP+A1kzAA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Nanyong Sun , Ryusuke Konishi , Andrew Morton , Linus Torvalds , Sasha Levin , linux-nilfs@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 08/12] nilfs2: fix NULL pointer in nilfs_##name##_attr_release Date: Mon, 13 Sep 2021 18:35:00 -0400 Message-Id: <20210913223504.436087-8-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210913223504.436087-1-sashal@kernel.org> References: <20210913223504.436087-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nanyong Sun [ Upstream commit dbc6e7d44a514f231a64d9d5676e001b660b6448 ] In nilfs_##name##_attr_release, kobj->parent should not be referenced because it is a NULL pointer. The release() method of kobject is always called in kobject_put(kobj), in the implementation of kobject_put(), the kobj->parent will be assigned as NULL before call the release() method. So just use kobj to get the subgroups, which is more efficient and can fix a NULL pointer reference problem. Link: https://lkml.kernel.org/r/20210629022556.3985106-3-sunnanyong@huawei.com Link: https://lkml.kernel.org/r/1625651306-10829-3-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Nanyong Sun Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- fs/nilfs2/sysfs.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/fs/nilfs2/sysfs.c b/fs/nilfs2/sysfs.c index cbfc132206e8..ca720d958315 100644 --- a/fs/nilfs2/sysfs.c +++ b/fs/nilfs2/sysfs.c @@ -64,11 +64,9 @@ static const struct sysfs_ops nilfs_##name##_attr_ops = { \ #define NILFS_DEV_INT_GROUP_TYPE(name, parent_name) \ static void nilfs_##name##_attr_release(struct kobject *kobj) \ { \ - struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \ - struct the_nilfs *nilfs = container_of(kobj->parent, \ - struct the_nilfs, \ - ns_##parent_name##_kobj); \ - subgroups = nilfs->ns_##parent_name##_subgroups; \ + struct nilfs_sysfs_##parent_name##_subgroups *subgroups = container_of(kobj, \ + struct nilfs_sysfs_##parent_name##_subgroups, \ + sg_##name##_kobj); \ complete(&subgroups->sg_##name##_kobj_unregister); \ } \ static struct kobj_type nilfs_##name##_ktype = { \ -- 2.30.2