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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 0CB44C2D0DB for ; Sat, 25 Jan 2020 20:25:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D3CE320708 for ; Sat, 25 Jan 2020 20:25:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726690AbgAYUZp (ORCPT ); Sat, 25 Jan 2020 15:25:45 -0500 Received: from smtp-out-no.shaw.ca ([64.59.134.9]:36318 "EHLO smtp-out-no.shaw.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726448AbgAYUZp (ORCPT ); Sat, 25 Jan 2020 15:25:45 -0500 Received: from cabot.adilger.int ([70.77.216.213]) by shaw.ca with ESMTP id vRzyisJvNkqGXvRzziDdFI; Sat, 25 Jan 2020 13:25:44 -0700 X-Authority-Analysis: v=2.3 cv=c/jVvi1l c=1 sm=1 tr=0 a=BQvS1EmAg2ttxjPVUuc1UQ==:117 a=BQvS1EmAg2ttxjPVUuc1UQ==:17 a=RPJ6JBhKAAAA:8 a=_CvfgrRZgBlTxnZNDbMA:9 a=fa_un-3J20JGBB2Tu-mn:22 From: Andreas Dilger To: tytso@mit.edu Cc: linux-ext4@vger.kernel.org, Andreas Dilger Subject: [PATCH] ext4: don't assume that mmp_nodename/bdevname have NUL Date: Sat, 25 Jan 2020 13:25:42 -0700 Message-Id: <1579983942-11927-1-git-send-email-adilger@dilger.ca> X-Mailer: git-send-email 1.8.0 X-CMAE-Envelope: MS4wfMHlIp+RiMhlSWRAiX58bb02uwmPWC9QHnxRVzJ2wHkykifLXnsNDbjBRgDcZFkNhZO2B3K8IK4shr3h96BycgWRLtJWSEwgQmt4YUG05FrhLuCcM+CY jpysTbHHwBLTXHg7evm68VK3X+0ayzHKj/iy+L54LmMQg7xRvEYKbtTWQMwMtB/O95KKZ8sMb/YI3UXe8esAqF58Xzm9iDLpfxK8VAgJGDuaEVWohdhO7kfR Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org 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. Signed-off-by: Andreas Dilger --- fs/ext4/mmp.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c index 2305b43..612476e 100644 --- a/fs/ext4/mmp.c +++ b/fs/ext4/mmp.c @@ -120,10 +120,10 @@ void __dump_mmp_msg(struct super_block *sb, struct mmp_struct *mmp, { __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", + (long long unsigned int)le64_to_cpu(mmp->mmp_time), + sizeof(mmp->mmp_nodename), mmp->mmp_nodename, + sizeof(mmp->mmp_bdevname), mmp->mmp_bdevname); } /* @@ -375,7 +375,8 @@ int ext4_multi_mount_protect(struct super_block *sb, /* * 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", + sizeof(mmp->mmp_bdevname), bdevname(bh->b_bdev, mmp->mmp_bdevname)); if (IS_ERR(EXT4_SB(sb)->s_mmp_tsk)) { -- 1.8.0