From nobody Fri Dec 19 18:52:09 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 21922FA3743 for ; Mon, 24 Oct 2022 13:11:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235555AbiJXNK7 (ORCPT ); Mon, 24 Oct 2022 09:10:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53802 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235436AbiJXNIm (ORCPT ); Mon, 24 Oct 2022 09:08:42 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 921839E680; Mon, 24 Oct 2022 05:21:52 -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 ams.source.kernel.org (Postfix) with ESMTPS id CB90EB81637; Mon, 24 Oct 2022 12:16:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2C958C433C1; Mon, 24 Oct 2022 12:16:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666613760; bh=uHn0RqWAGuY2UsCqYwefavnRuYHwaMKMXxufWpPwynk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LsFiuBzX44km6J6UEJj/6G6ZRTrwmDKC7QLmMd0C7VEMVqKqkwIdHQVEMBUgGWnfl qMLzjqEfKS92BPX9IfMDouq1mRTM6BKdNYVGaxZguiLIEvQQDyAgymKROvXhmYlNo8 UuvDItQDEVyHn5sHb4chVU7MF83p0lWi3aIo5fM8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Kelley , Guoqing Jiang , Saurabh Sengar , Song Liu Subject: [PATCH 5.4 252/255] md: Replace snprintf with scnprintf Date: Mon, 24 Oct 2022 13:32:42 +0200 Message-Id: <20221024113011.699767171@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024113002.471093005@linuxfoundation.org> References: <20221024113002.471093005@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Saurabh Sengar commit 1727fd5015d8f93474148f94e34cda5aa6ad4a43 upstream. Current code produces a warning as shown below when total characters in the constituent block device names plus the slashes exceeds 200. snprintf() returns the number of characters generated from the given input, which could cause the expression =E2=80=9C200 =E2=80=93 len=E2=80=9D= to wrap around to a large positive number. Fix this by using scnprintf() instead, which returns the actual number of characters written into the buffer. [ 1513.267938] ------------[ cut here ]------------ [ 1513.267943] WARNING: CPU: 15 PID: 37247 at /lib/vsprintf.c:2509 vs= nprintf+0x2c8/0x510 [ 1513.267944] Modules linked in: [ 1513.267969] CPU: 15 PID: 37247 Comm: mdadm Not tainted 5.4.0-1085-azure = #90~18.04.1-Ubuntu [ 1513.267969] Hardware name: Microsoft Corporation Virtual Machine/Virtual= Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022 [ 1513.267971] RIP: 0010:vsnprintf+0x2c8/0x510 <-snip-> [ 1513.267982] Call Trace: [ 1513.267986] snprintf+0x45/0x70 [ 1513.267990] ? disk_name+0x71/0xa0 [ 1513.267993] dump_zones+0x114/0x240 [raid0] [ 1513.267996] ? _cond_resched+0x19/0x40 [ 1513.267998] raid0_run+0x19e/0x270 [raid0] [ 1513.268000] md_run+0x5e0/0xc50 [ 1513.268003] ? security_capable+0x3f/0x60 [ 1513.268005] do_md_run+0x19/0x110 [ 1513.268006] md_ioctl+0x195e/0x1f90 [ 1513.268007] blkdev_ioctl+0x91f/0x9f0 [ 1513.268010] block_ioctl+0x3d/0x50 [ 1513.268012] do_vfs_ioctl+0xa9/0x640 [ 1513.268014] ? __fput+0x162/0x260 [ 1513.268016] ksys_ioctl+0x75/0x80 [ 1513.268017] __x64_sys_ioctl+0x1a/0x20 [ 1513.268019] do_syscall_64+0x5e/0x200 [ 1513.268021] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 766038846e875 ("md/raid0: replace printk() with pr_*()") Reviewed-by: Michael Kelley Acked-by: Guoqing Jiang Signed-off-by: Saurabh Sengar Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid0.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -63,8 +63,8 @@ static void dump_zones(struct mddev *mdd int len =3D 0; =20 for (k =3D 0; k < conf->strip_zone[j].nb_dev; k++) - len +=3D snprintf(line+len, 200-len, "%s%s", k?"/":"", - bdevname(conf->devlist[j*raid_disks + len +=3D scnprintf(line+len, 200-len, "%s%s", k?"/":"", + bdevname(conf->devlist[j*raid_disks + k]->bdev, b)); pr_debug("md: zone%d=3D[%s]\n", j, line); =20