From patchwork Thu Oct 16 01:53:39 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gui Hecheng X-Patchwork-Id: 5087611 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id DB0A8C11AD for ; Thu, 16 Oct 2014 01:54:56 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0C436200FF for ; Thu, 16 Oct 2014 01:54:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 21F9C20155 for ; Thu, 16 Oct 2014 01:54:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752035AbaJPByu (ORCPT ); Wed, 15 Oct 2014 21:54:50 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:29942 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751484AbaJPByt (ORCPT ); Wed, 15 Oct 2014 21:54:49 -0400 X-IronPort-AV: E=Sophos;i="5.04,729,1406563200"; d="scan'208";a="37408791" Received: from localhost (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 16 Oct 2014 09:51:43 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id s9G1sjpi001316 for ; Thu, 16 Oct 2014 09:54:45 +0800 Received: from localhost.localdomain (10.167.226.111) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.181.6; Thu, 16 Oct 2014 09:54:59 +0800 From: Gui Hecheng To: CC: Gui Hecheng Subject: [PATCH] btrfs-progs: prevent silent damage when add dev to an invalid mntpnt Date: Thu, 16 Oct 2014 09:53:39 +0800 Message-ID: <1413424419-15237-3-git-send-email-guihc.fnst@cn.fujitsu.com> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1413424419-15237-1-git-send-email-guihc.fnst@cn.fujitsu.com> References: <1413424419-15237-1-git-send-email-guihc.fnst@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.111] Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Problem: # mkfs.btrfs -f /dev/sda1 # btrfs dev add /dev/sda1 /dir -f <== dir is not a mntpnt btrfs dev add just report invalid ioctl but it has already made changes to /dev/sda1 with @btrfs_prepare_device(), so the fs on /dev/sda1 is damaged. We could check whether /dev/sda1 is a valid mntpnt by calling @find_mount_root() to prevent this silent damage. Signed-off-by: Gui Hecheng --- cmds-device.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/cmds-device.c b/cmds-device.c index a728f21..65815c3 100644 --- a/cmds-device.c +++ b/cmds-device.c @@ -53,6 +53,7 @@ static int cmd_add_dev(int argc, char **argv) int discard = 1; int force = 0; char estr[100]; + char rmntpnt[PATH_MAX]; while (1) { int long_index; @@ -84,6 +85,22 @@ static int cmd_add_dev(int argc, char **argv) mntpnt = argv[optind + argc - 1]; + if (!realpath(mntpnt, rmntpnt)) { + fprintf(stderr, "ERROR: %s\n", strerror(errno)); + return 1; + } + + ret = find_mount_root(rmntpnt, &mntpnt); + if (ret < 0) { + fprintf(stderr, "ERROR: find_mount_root failed on '%s': %s\n", + rmntpnt, strerror(-ret)); + return 1; + } else if (ret > 0) { + fprintf(stderr, "ERROR: '%s' doesn't belong to btrfs mount point\n", + rmntpnt); + return 1; + } + fdmnt = open_file_or_dir(mntpnt, &dirstream); if (fdmnt < 0) { fprintf(stderr, "ERROR: can't access '%s'\n", mntpnt);