From nobody Tue Dec 16 15:37:13 2025 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 4B24EC25B48 for ; Fri, 27 Oct 2023 01:16:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229694AbjJ0BQF (ORCPT ); Thu, 26 Oct 2023 21:16:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60282 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229604AbjJ0BQD (ORCPT ); Thu, 26 Oct 2023 21:16:03 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC14B1BB for ; Thu, 26 Oct 2023 18:16:00 -0700 (PDT) Received: from dggpemm500009.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4SGl5q4bdPzrTlN; Fri, 27 Oct 2023 09:13:03 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpemm500009.china.huawei.com (7.185.36.225) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Fri, 27 Oct 2023 09:15:58 +0800 From: ZhaoLong Wang To: , , , , CC: , , , , , Subject: [PATCH v3] mtd: Fix gluebi NULL pointer dereference caused by ftl notifier Date: Fri, 27 Oct 2023 09:20:33 +0800 Message-ID: <20231027012033.50280-1-wangzhaolong1@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500009.china.huawei.com (7.185.36.225) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If both flt.ko and gluebi.ko are loaded, the notiier of ftl triggers NULL pointer dereference when trying to access =E2=80=98gluebi->desc=E2=80=99 in gluebi_read(). ubi_gluebi_init ubi_register_volume_notifier ubi_enumerate_volumes ubi_notify_all gluebi_notify nb->notifier_call() gluebi_create mtd_device_register mtd_device_parse_register add_mtd_device blktrans_notify_add not->add() ftl_add_mtd tr->add_mtd() scan_header mtd_read mtd_read_oob mtd_read_oob_std gluebi_read mtd->read() gluebi->desc - NULL Detailed reproduction information available at the link[1], The solution for the gluebi module is to run jffs2 on the UBI volume without considering working with ftl or mtdblock.[2]. Therefore, this problem can be avoided by preventing gluebi from creating mtdblock devices. Fixes: 2ba3d76a1e29 ("UBI: make gluebi a separate module") Link: https://bugzilla.kernel.org/show_bug.cgi?id=3D217992 [1] Link: https://lore.kernel.org/lkml/441107100.23734.1697904580252.JavaMail.z= imbra@nod.at/ [2] Signed-off-by: ZhaoLong Wang Acked-by: Richard Weinberger Reviewed-by: Zhihao Cheng --- drivers/mtd/mtd_blkdevs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c index ff18636e0889..5bc32108ca03 100644 --- a/drivers/mtd/mtd_blkdevs.c +++ b/drivers/mtd/mtd_blkdevs.c @@ -463,7 +463,7 @@ static void blktrans_notify_add(struct mtd_info *mtd) { struct mtd_blktrans_ops *tr; =20 - if (mtd->type =3D=3D MTD_ABSENT) + if (mtd->type =3D=3D MTD_ABSENT || mtd->type =3D=3D MTD_UBIVOLUME) return; =20 list_for_each_entry(tr, &blktrans_majors, list) @@ -503,7 +503,7 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr) mutex_lock(&mtd_table_mutex); list_add(&tr->list, &blktrans_majors); mtd_for_each_device(mtd) - if (mtd->type !=3D MTD_ABSENT) + if (mtd->type !=3D MTD_ABSENT && mtd->type !=3D MTD_UBIVOLUME) tr->add_mtd(tr, mtd); mutex_unlock(&mtd_table_mutex); return 0; --=20 2.31.1