From nobody Fri Oct 17 10:12:37 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 A4F06C4332F for ; Wed, 19 Oct 2022 09:36:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233974AbiJSJg5 (ORCPT ); Wed, 19 Oct 2022 05:36:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233972AbiJSJaH (ORCPT ); Wed, 19 Oct 2022 05:30:07 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28D22EB752; Wed, 19 Oct 2022 02:13:17 -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 8FA6F617D1; Wed, 19 Oct 2022 09:02:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A2203C43470; Wed, 19 Oct 2022 09:02:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666170154; bh=Fbe3KMtCdsW7s2zZrX5blXwHhz1QzTcZnQm6f1z/NVM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qHyfjAamgIDObNW3C+qYaKh5xF9vC8pUq+q4WjLNbbdUT0Ssl+r37FGTZfJXm1+/q lr6wfogzXrKBTH1NCJeV4QekPj/AC+jhAdl5TLVmgQPZYfAH7LYeXxubrCvxTI0tDH ldUC7q1DX/GvZahoSsH/NJTdu2bIKqFidn3WIxbo= 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 , Sasha Levin Subject: [PATCH 6.0 547/862] md: Replace snprintf with scnprintf Date: Wed, 19 Oct 2022 10:30:34 +0200 Message-Id: <20221019083314.124312910@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221019083249.951566199@linuxfoundation.org> References: <20221019083249.951566199@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 [ Upstream commit 1727fd5015d8f93474148f94e34cda5aa6ad4a43 ] 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: Sasha Levin --- drivers/md/raid0.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index 78addfe4a0c9..857c49399c28 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -47,7 +47,7 @@ static void dump_zones(struct mddev *mddev) 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%pg", k?"/":"", + len +=3D scnprintf(line+len, 200-len, "%s%pg", k?"/":"", conf->devlist[j * raid_disks + k]->bdev); pr_debug("md: zone%d=3D[%s]\n", j, line); =20 --=20 2.35.1