From nobody Fri Dec 19 20:50:51 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 A68C2C32772 for ; Tue, 23 Aug 2022 10:08:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352762AbiHWKIu (ORCPT ); Tue, 23 Aug 2022 06:08:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43446 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352563AbiHWKCH (ORCPT ); Tue, 23 Aug 2022 06:02:07 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8D2907C330; Tue, 23 Aug 2022 01:50:04 -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 012F761386; Tue, 23 Aug 2022 08:50:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E4854C43470; Tue, 23 Aug 2022 08:50:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661244603; bh=e+yJzTQerwJUBXmocqiz1bulRsPaY47NFWa5KTCk2WM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EG+bqQhUiDnE6DM745jBTJu6SKoQ+Vuoz4AvQn3Uie0qQ+mrC5Al/I6VFV9GxYQRS 8g9MYWXzWJFbRAJoklzS+ZGh8QwqVHUjp2YOzbPZMQ79OUDEUnCaDO+605TsQnT8Ex F3NCgQi3eFUx3UOWGppFM29QZh4IcRKVw0mF3lWA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , Mike Snitzer Subject: [PATCH 4.14 163/229] dm raid: fix address sanitizer warning in raid_status Date: Tue, 23 Aug 2022 10:25:24 +0200 Message-Id: <20220823080059.492496579@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080053.202747790@linuxfoundation.org> References: <20220823080053.202747790@linuxfoundation.org> User-Agent: quilt/0.67 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: Mikulas Patocka commit 1fbeea217d8f297fe0e0956a1516d14ba97d0396 upstream. There is this warning when using a kernel with the address sanitizer and running this testsuite: https://gitlab.com/cki-project/kernel-tests/-/tree/main/storage/swraid/scsi= _raid =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D BUG: KASAN: slab-out-of-bounds in raid_status+0x1747/0x2820 [dm_raid] Read of size 4 at addr ffff888079d2c7e8 by task lvcreate/13319 CPU: 0 PID: 13319 Comm: lvcreate Not tainted 5.18.0-0.rc3. #1 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 Call Trace: dump_stack_lvl+0x6a/0x9c print_address_description.constprop.0+0x1f/0x1e0 print_report.cold+0x55/0x244 kasan_report+0xc9/0x100 raid_status+0x1747/0x2820 [dm_raid] dm_ima_measure_on_table_load+0x4b8/0xca0 [dm_mod] table_load+0x35c/0x630 [dm_mod] ctl_ioctl+0x411/0x630 [dm_mod] dm_ctl_ioctl+0xa/0x10 [dm_mod] __x64_sys_ioctl+0x12a/0x1a0 do_syscall_64+0x5b/0x80 The warning is caused by reading conf->max_nr_stripes in raid_status. The code in raid_status reads mddev->private, casts it to struct r5conf and reads the entry max_nr_stripes. However, if we have different raid type than 4/5/6, mddev->private doesn't point to struct r5conf; it may point to struct r0conf, struct r1conf, struct r10conf or struct mpconf. If we cast a pointer to one of these structs to struct r5conf, we will be reading invalid memory and KASAN warns about it. Fix this bug by reading struct r5conf only if raid type is 4, 5 or 6. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-raid.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -3394,7 +3394,7 @@ static void raid_status(struct dm_target { struct raid_set *rs =3D ti->private; struct mddev *mddev =3D &rs->md; - struct r5conf *conf =3D mddev->private; + struct r5conf *conf =3D rs_is_raid456(rs) ? mddev->private : NULL; int i, max_nr_stripes =3D conf ? conf->max_nr_stripes : 0; bool array_in_sync; unsigned int raid_param_cnt =3D 1; /* at least 1 for chunksize */