From patchwork Fri Sep 26 07:36:35 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 4979071 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 29FFDBEEA6 for ; Fri, 26 Sep 2014 07:36:43 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4EE0220265 for ; Fri, 26 Sep 2014 07:36:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 66D2020221 for ; Fri, 26 Sep 2014 07:36:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753378AbaIZHgh (ORCPT ); Fri, 26 Sep 2014 03:36:37 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:45424 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1753048AbaIZHgh (ORCPT ); Fri, 26 Sep 2014 03:36:37 -0400 X-IronPort-AV: E=Sophos;i="5.04,603,1406563200"; d="scan'208";a="36507224" Received: from localhost (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 26 Sep 2014 15:33:35 +0800 Received: from G08CNEXCHPEKD02.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id s8Q7adnA024215 for ; Fri, 26 Sep 2014 15:36:40 +0800 Received: from adam-work.lan (10.167.226.33) by G08CNEXCHPEKD02.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.181.6; Fri, 26 Sep 2014 15:36:36 +0800 From: Qu Wenruo To: Subject: [PATCH] btrfs-progs: Check the consistence between the parent node and child node/leaf. Date: Fri, 26 Sep 2014 15:36:35 +0800 Message-ID: <1411716995-22537-1-git-send-email-quwenruo@cn.fujitsu.com> X-Mailer: git-send-email 2.1.1 MIME-Version: 1.0 X-Originating-IP: [10.167.226.33] Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, 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 When btrfs-progs walk down the tree, it does not check whether the child node/leaf is valid. In fact, there is some corrupted image whose csum is all valid but parent node points to a invalid leaf. In my case, the parent node in fs tree point to a invalid leaf(gen 11), whose generation(15) and first key(EXTENT_TREE ROOT_ITEM 0) is completely invalid, and will cause BUG_ON in process_inode_item(). Unfortunately, we are unable to fix when it happens. So we can only output meaningful error message and avoid the insane node/leaf, which is still much better than the original BUG_ON(). Signed-off-by: Qu Wenruo --- cmds-check.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) diff --git a/cmds-check.c b/cmds-check.c index d479361..9471709 100644 --- a/cmds-check.c +++ b/cmds-check.c @@ -1302,6 +1302,52 @@ static void reada_walk_down(struct btrfs_root *root, } } +/* + * Check the child node/leaf by the following condition: + * 1. the first item key of the node/leaf should be the same with the one + * in parent. + * 2. block in parent node should match the child node/leaf. + * 3. generation of parent node and child's header should be consistent. + * + * Or the child node/leaf pointed by the key in parent is not valid. + * + * We hope to check leaf owner too, but since subvol may share leaves, + * which makes leaf owner check not so strong, key check should be + * sufficient enough for that case. + */ +static int check_child_node(struct btrfs_root *root, + struct extent_buffer *parent, int slot, + struct extent_buffer *child) +{ + struct btrfs_key parent_key; + struct btrfs_key child_key; + int ret = 0; + + btrfs_item_key_to_cpu(parent, &parent_key, slot); + btrfs_item_key_to_cpu(child, &child_key, 0); + if (memcmp(&parent_key, &child_key, sizeof(parent_key))) { + ret = -EINVAL; + fprintf(stderr, + "Wrong key of child node/leaf, wanted: (%llu, %u, %llu), have: (%llu, %u, %llu)\n", + parent_key.objectid, parent_key.type, parent_key.offset, + child_key.objectid, child_key.type, child_key.offset); + } + if (btrfs_header_bytenr(child) != btrfs_node_blockptr(parent, slot)) { + ret = -EINVAL; + fprintf(stderr, "Wrong block of child node/leaf, wanted: %llu, have: %llu\n", + btrfs_node_blockptr(parent, slot), + btrfs_header_bytenr(child)); + } + if (btrfs_node_ptr_generation(parent, slot) != + btrfs_header_generation(child)) { + ret = -EINVAL; + fprintf(stderr, "Wrong generation of child node/leaf, wanted: %llu, have: %llu\n", + btrfs_header_generation(child), + btrfs_node_ptr_generation(parent, slot)); + } + return ret; +} + static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path, struct walk_control *wc, int *level) { @@ -1375,6 +1421,11 @@ static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path, } } + ret = check_child_node(root, cur, path->slots[*level], next); + if (ret) { + err = ret; + goto out; + } *level = *level - 1; free_extent_buffer(path->nodes[*level]); path->nodes[*level] = next;