From patchwork Tue Jul 3 09:10:09 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 10503537 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id C7FD86035E for ; Tue, 3 Jul 2018 09:10:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B7A85289A6 for ; Tue, 3 Jul 2018 09:10:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AB86C289BE; Tue, 3 Jul 2018 09:10:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 20C4E289A6 for ; Tue, 3 Jul 2018 09:10:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932517AbeGCJKV (ORCPT ); Tue, 3 Jul 2018 05:10:21 -0400 Received: from mx2.suse.de ([195.135.220.15]:59994 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754536AbeGCJKU (ORCPT ); Tue, 3 Jul 2018 05:10:20 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 7FA64AD6F for ; Tue, 3 Jul 2018 09:10:19 +0000 (UTC) From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH 5/5] btrfs: Verify every chunk has corresponding block group at mount time Date: Tue, 3 Jul 2018 17:10:09 +0800 Message-Id: <20180703091009.16399-6-wqu@suse.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180703091009.16399-1-wqu@suse.com> References: <20180703091009.16399-1-wqu@suse.com> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If a crafted btrfs has missing block group items, it could cause unexpected behavior and breaks our expectation on 1:1 chunk<->block group mapping. Although we added block group -> chunk mapping check, we still need chunk -> block group mapping check. This patch will do extra check to ensure each chunk has its corresponding block group. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199847 Reported-by: Xu Wen Signed-off-by: Qu Wenruo Reviewed-by: Gu Jinxiang --- fs/btrfs/extent-tree.c | 52 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 51 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 82b446f014b9..746095034ca2 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -10038,6 +10038,56 @@ static int check_exist_chunk(struct btrfs_fs_info *fs_info, u64 start, u64 len, return ret; } +/* + * Iterate all chunks and verify each of them has corresponding block group + */ +static int check_chunk_block_group_mappings(struct btrfs_fs_info *fs_info) +{ + struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; + struct extent_map *em; + struct btrfs_block_group_cache *bg; + u64 start = 0; + int ret = 0; + + while (1) { + read_lock(&map_tree->map_tree.lock); + em = lookup_extent_mapping(&map_tree->map_tree, start, + (u64)-1 - start); + read_unlock(&map_tree->map_tree.lock); + if (!em) + break; + + bg = btrfs_lookup_block_group(fs_info, em->start); + if (!bg) { + btrfs_err_rl(fs_info, + "chunk start=%llu len=%llu doesn't have corresponding block group", + em->start, em->len); + ret = -ENOENT; + free_extent_map(em); + break; + } + if (bg->key.objectid != em->start || + bg->key.offset != em->len || + (bg->flags & BTRFS_BLOCK_GROUP_TYPE_MASK) != + (em->map_lookup->type & BTRFS_BLOCK_GROUP_TYPE_MASK)) { + btrfs_err_rl(fs_info, +"chunk start=%llu len=%llu flags=0x%llx doesn't match with block group start=%llu len=%llu flags=0x%llx", + em->start, em->len, + em->map_lookup->type & BTRFS_BLOCK_GROUP_TYPE_MASK, + bg->key.objectid, bg->key.offset, + bg->flags & BTRFS_BLOCK_GROUP_TYPE_MASK); + ret = -EUCLEAN; + free_extent_map(em); + btrfs_put_block_group(bg); + break; + } + start = em->start + em->len; + free_extent_map(em); + btrfs_put_block_group(bg); + } + return ret; +} + int btrfs_read_block_groups(struct btrfs_fs_info *info) { struct btrfs_path *path; @@ -10227,7 +10277,7 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info) btrfs_add_raid_kobjects(info); init_global_block_rsv(info); - ret = 0; + ret = check_chunk_block_group_mappings(info); error: btrfs_free_path(path); return ret;