From patchwork Mon Nov 11 14:43:46 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guiyao X-Patchwork-Id: 1192968 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-ext4-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=huawei.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 47BYXy0PFcz9sPn for ; Tue, 12 Nov 2019 01:44:02 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727015AbfKKOoB (ORCPT ); Mon, 11 Nov 2019 09:44:01 -0500 Received: from szxga08-in.huawei.com ([45.249.212.255]:36924 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726832AbfKKOoB (ORCPT ); Mon, 11 Nov 2019 09:44:01 -0500 Received: from DGGEMM406-HUB.china.huawei.com (unknown [172.30.72.56]) by Forcepoint Email with ESMTP id ACF0049714017543CCD7; Mon, 11 Nov 2019 22:43:54 +0800 (CST) Received: from DGGEMM512-MBS.china.huawei.com ([169.254.4.39]) by DGGEMM406-HUB.china.huawei.com ([10.3.20.214]) with mapi id 14.03.0439.000; Mon, 11 Nov 2019 22:43:47 +0800 From: Guiyao To: "Theodore Y. Ts'o" CC: "linux-ext4@vger.kernel.org" , Mingfangsen , "ebiggers@google.com" , "aceballos@gmail.com" , "vertaling@coevern.nl" Subject: =?gb2312?b?tPC4tDogW1BBVENIIHYyXSBlMmZzcHJvZ3M6IENoZWNrIGRldmlj?= =?gb2312?b?ZSBpZCBpbiBhZHZhbmNlIHRvIHNraXAgZmFrZSBkZXZpY2UgbmFt?= =?gb2312?b?ZQ==?= Thread-Topic: [PATCH v2] e2fsprogs: Check device id in advance to skip fake device name Thread-Index: AdWYmobA6kLp3Wt1RVKDbvNk/crgBQ== Date: Mon, 11 Nov 2019 14:43:46 +0000 Message-ID: <005F77DB9A260B4E91664DDF22573C66E9D380C7@dggemm512-mbs.china.huawei.com> Accept-Language: zh-CN, en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.173.220.158] MIME-Version: 1.0 X-CFilter-Loop: Reflected Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Hi Theodore, Thanks for your response and your rewriting. Actually, we found some insane system administrators, they not only do something like "mount -t tmpfs /dev/sdb /tmp ", but also they do " ln -s /dev/sdb abc ", then "resize2fs abc xxx". :( So we have to add the fixing code in both sides of "name matched" and "name not matched". For the compiling issue, it's my fault in previous patch, and added the macro in a wrong line. So, I rewrote it again, and please give more advise. Thank you in advance. diff --git a/lib/ext2fs/ismounted.c b/lib/ext2fs/ismounted.c index 6cd497d..729769e 100644 --- a/lib/ext2fs/ismounted.c +++ b/lib/ext2fs/ismounted.c @@ -97,6 +97,9 @@ static errcode_t check_mntent_file(const char *mtab_file, const char *file, int *mount_flags, char *mtpt, int mtlen) { struct mntent *mnt; +#ifndef __GNU__ + struct stat dir_st_buf; +#endif /* __GNU__ */ struct stat st_buf; errcode_t retval = 0; dev_t file_dev=0, file_rdev=0; @@ -128,13 +131,32 @@ static errcode_t check_mntent_file(const char *mtab_file, const char *file, while ((mnt = getmntent (f)) != NULL) { if (mnt->mnt_fsname[0] != '/') continue; - if (strcmp(file, mnt->mnt_fsname) == 0) +#ifndef __GNU__ + if (stat(mnt->mnt_dir, &dir_st_buf) != 0) + continue; +#endif + if (strcmp(file, mnt->mnt_fsname) == 0) { +#ifndef __GNU__ + if (file_rdev && (file_rdev != dir_st_buf.st_dev)) { +#ifdef DEBUG + printf("Bogus entry in %s! " + "(%s does not exist)\n", + mtab_file, mnt->mnt_dir); +#endif /* DEBUG */ + continue; + } +#endif /* __GNU__ */ break; + } + if (stat(mnt->mnt_fsname, &st_buf) == 0) { if (ext2fsP_is_disk_device(st_buf.st_mode)) { #ifndef __GNU__ - if (file_rdev && (file_rdev == st_buf.st_rdev)) - break; + if (file_rdev && (file_rdev == st_buf.st_rdev)) { + if (file_rdev == dir_st_buf.st_dev) + break; + } + if (check_loop_mounted(mnt->mnt_fsname, st_buf.st_rdev, file_dev, file_ino) == 1) @@ -168,32 +190,6 @@ static errcode_t check_mntent_file(const char *mtab_file, const char *file, #endif /* __GNU__ */ goto errout; } -#ifndef __GNU__ /* The GNU hurd is deficient; what else is new? */ - /* Validate the entry in case /etc/mtab is out of date */ - /* - * We need to be paranoid, because some broken distributions - * (read: Slackware) don't initialize /etc/mtab before checking - * all of the non-root filesystems on the disk. - */ - if (stat(mnt->mnt_dir, &st_buf) < 0) { - retval = errno; - if (retval == ENOENT) { -#ifdef DEBUG - printf("Bogus entry in %s! (%s does not exist)\n", - mtab_file, mnt->mnt_dir); -#endif /* DEBUG */ - retval = 0; - } - goto errout; - } - if (file_rdev && (st_buf.st_dev != file_rdev)) { -#ifdef DEBUG - printf("Bogus entry in %s! (%s not mounted on %s)\n", - mtab_file, file, mnt->mnt_dir); -#endif /* DEBUG */ - goto errout; - } -#endif /* __GNU__ */ *mount_flags = EXT2_MF_MOUNTED; #ifdef MNTOPT_RO