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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 21E75C35677 for ; Thu, 27 Feb 2020 14:40:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E51FC2468F for ; Thu, 27 Feb 2020 14:40:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582814453; bh=EwYfUOnmtfFffy16it4zCFunWeADkB2Shz4MSOMEUtc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=L17cLx39Rjg/7Egjm7KDAQWnFtGJySnaOw+kyWQ/kqZiPDxxc0Cc7g1ivj7iUy8e0 fcK4XX/BctbPtzmrDwuHbzQfmD5FTyNBuVPlHu55I3/m1jHswUDERdLMOqOpM7jBS9 7M4JDHO4QpQrxzAdTgNvPpWa7+dmPKdEE+YAv+us= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731836AbgB0Okv (ORCPT ); Thu, 27 Feb 2020 09:40:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:52314 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731561AbgB0Nwm (ORCPT ); Thu, 27 Feb 2020 08:52:42 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8748C21D7E; Thu, 27 Feb 2020 13:52:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582811562; bh=EwYfUOnmtfFffy16it4zCFunWeADkB2Shz4MSOMEUtc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wW2/QdRkt3PZ566YgymFaDS/dAs6Z1gkzHPBKEs+A2XmpM2EaLSxPfw3Tkozwqwxj Gy6XYP7nZXQXBVugRU3/QjgpQbNTlnMyOtAIZZXWRodxsxJ73cFuHeAO/JbqS6WglK GEucHP9ce4XkWy4plotLKGGSiMsIaQPUi4rZXKg0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andreas Dilger , Theodore Tso , stable@kernel.org Subject: [PATCH 4.14 015/237] ext4: dont assume that mmp_nodename/bdevname have NUL Date: Thu, 27 Feb 2020 14:33:49 +0100 Message-Id: <20200227132257.164230443@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200227132255.285644406@linuxfoundation.org> References: <20200227132255.285644406@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andreas Dilger commit 14c9ca0583eee8df285d68a0e6ec71053efd2228 upstream. Don't assume that the mmp_nodename and mmp_bdevname strings are NUL terminated, since they are filled in by snprintf(), which is not guaranteed to do so. Link: https://lore.kernel.org/r/1580076215-1048-1-git-send-email-adilger@dilger.ca Signed-off-by: Andreas Dilger Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman --- fs/ext4/mmp.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/fs/ext4/mmp.c +++ b/fs/ext4/mmp.c @@ -120,10 +120,10 @@ void __dump_mmp_msg(struct super_block * { __ext4_warning(sb, function, line, "%s", msg); __ext4_warning(sb, function, line, - "MMP failure info: last update time: %llu, last update " - "node: %s, last update device: %s", - (long long unsigned int) le64_to_cpu(mmp->mmp_time), - mmp->mmp_nodename, mmp->mmp_bdevname); + "MMP failure info: last update time: %llu, last update node: %.*s, last update device: %.*s", + (unsigned long long)le64_to_cpu(mmp->mmp_time), + (int)sizeof(mmp->mmp_nodename), mmp->mmp_nodename, + (int)sizeof(mmp->mmp_bdevname), mmp->mmp_bdevname); } /* @@ -154,6 +154,7 @@ static int kmmpd(void *data) mmp_check_interval = max(EXT4_MMP_CHECK_MULT * mmp_update_interval, EXT4_MMP_MIN_CHECK_INTERVAL); mmp->mmp_check_interval = cpu_to_le16(mmp_check_interval); + BUILD_BUG_ON(sizeof(mmp->mmp_bdevname) < BDEVNAME_SIZE); bdevname(bh->b_bdev, mmp->mmp_bdevname); memcpy(mmp->mmp_nodename, init_utsname()->nodename, @@ -375,7 +376,8 @@ skip: /* * Start a kernel thread to update the MMP block periodically. */ - EXT4_SB(sb)->s_mmp_tsk = kthread_run(kmmpd, mmpd_data, "kmmpd-%s", + EXT4_SB(sb)->s_mmp_tsk = kthread_run(kmmpd, mmpd_data, "kmmpd-%.*s", + (int)sizeof(mmp->mmp_bdevname), bdevname(bh->b_bdev, mmp->mmp_bdevname)); if (IS_ERR(EXT4_SB(sb)->s_mmp_tsk)) {