From patchwork Wed Nov 8 00:54:25 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 10047487 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 7692560247 for ; Wed, 8 Nov 2017 00:54:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 69CF72A269 for ; Wed, 8 Nov 2017 00:54:58 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5E7A22A291; Wed, 8 Nov 2017 00:54:58 +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=-6.9 required=2.0 tests=BAYES_00,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 CD4222A291 for ; Wed, 8 Nov 2017 00:54:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933803AbdKHAyz (ORCPT ); Tue, 7 Nov 2017 19:54:55 -0500 Received: from victor.provo.novell.com ([137.65.250.26]:60248 "EHLO prv3-mh.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933452AbdKHAyy (ORCPT ); Tue, 7 Nov 2017 19:54:54 -0500 Received: from adam-pc.lan (prv-ext-foundry1int.gns.novell.com [137.65.251.240]) by prv3-mh.provo.novell.com with ESMTP (NOT encrypted); Tue, 07 Nov 2017 17:54:41 -0700 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: dsterba@suse.cz Subject: [PATCH v2 2/3] btrfs: tree-checker: Add checker for dir item Date: Wed, 8 Nov 2017 08:54:25 +0800 Message-Id: <20171108005426.17903-3-wqu@suse.com> X-Mailer: git-send-email 2.15.0 In-Reply-To: <20171108005426.17903-1-wqu@suse.com> References: <20171108005426.17903-1-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 Add checker for dir item, for key types DIR_ITEM, DIR_INDEX and XATTR_ITEM. This checker does comprehensive check for: 1) dir_item header and its data size Against item boundary and maximum name/xattr length. This part is mostly the same as old verify_dir_item(). 2) dir_type Against maximum file types, and against key type. Since XATTR key should only have FT_XATTR dir item, and normal dir item type should not have XATTR key. The check between key->type and dir_type is newly introduced by this patch. 3) name hash For XATTR and DIR_ITEM key, key->offset is name hash (crc32). Check the hash of name against key to ensure it's correct. The name hash check is only found in btrfs-progs before this patch. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba --- fs/btrfs/tree-checker.c | 141 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 141 insertions(+) diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index ce4ed6ec8f39..66dac0a4b01f 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -30,6 +30,7 @@ #include "tree-checker.h" #include "disk-io.h" #include "compression.h" +#include "hash.h" /* * Error message should follow the following format: @@ -222,6 +223,141 @@ static int check_csum_item(struct btrfs_root *root, struct extent_buffer *leaf, return 0; } +/* + * Customized reported for dir_item, only important new info is key->objectid, + * which represents inode number + */ +__printf(4, 5) +static void dir_item_err(const struct btrfs_root *root, + const struct extent_buffer *eb, int slot, + const char *fmt, ...) +{ + struct btrfs_key key; + struct va_format vaf; + va_list args; + + btrfs_item_key_to_cpu(eb, &key, slot); + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + btrfs_crit(root->fs_info, + "corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV", + btrfs_header_level(eb) == 0 ? "leaf" : "node", root->objectid, + btrfs_header_bytenr(eb), slot, key.objectid, &vaf); + va_end(args); +} + +static int check_dir_item(struct btrfs_root *root, + struct extent_buffer *leaf, + struct btrfs_key *key, int slot) +{ + struct btrfs_dir_item *di; + u32 item_size = btrfs_item_size_nr(leaf, slot); + u32 cur = 0; + + di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); + while (cur < item_size) { + char namebuf[max(BTRFS_NAME_LEN, XATTR_NAME_MAX)]; + u32 name_len; + u32 data_len; + u32 max_name_len; + u32 total_size; + u32 name_hash; + u8 dir_type; + + /* header itself should not cross item boundary */ + if (cur + sizeof(*di) > item_size) { + dir_item_err(root, leaf, slot, + "dir item header crosses item boundary, have %lu boundary %u", + cur + sizeof(*di), item_size); + return -EUCLEAN; + } + + /* dir type check */ + dir_type = btrfs_dir_type(leaf, di); + if (dir_type >= BTRFS_FT_MAX) { + dir_item_err(root, leaf, slot, + "invalid dir item type, have %u expect [0, %u)", + dir_type, BTRFS_FT_MAX); + return -EUCLEAN; + } + + if (key->type == BTRFS_XATTR_ITEM_KEY && + dir_type != BTRFS_FT_XATTR) { + dir_item_err(root, leaf, slot, + "invalid dir item type for XATTR key, have %u expect %u", + dir_type, BTRFS_FT_XATTR); + return -EUCLEAN; + } + if (dir_type == BTRFS_FT_XATTR && + key->type != BTRFS_XATTR_ITEM_KEY) { + dir_item_err(root, leaf, slot, + "xattr dir type found for non-XATTR key"); + return -EUCLEAN; + } + if (dir_type == BTRFS_FT_XATTR) + max_name_len = XATTR_NAME_MAX; + else + max_name_len = BTRFS_NAME_LEN; + + /* Name/data length check */ + name_len = btrfs_dir_name_len(leaf, di); + data_len = btrfs_dir_data_len(leaf, di); + if (name_len > max_name_len) { + dir_item_err(root, leaf, slot, + "dir item name len too long, have %u max %u", + name_len, max_name_len); + return -EUCLEAN; + } + if (name_len + data_len > BTRFS_MAX_XATTR_SIZE(root->fs_info)) { + dir_item_err(root, leaf, slot, + "dir item name and data len too long, have %u max %u", + name_len + data_len, + BTRFS_MAX_XATTR_SIZE(root->fs_info)); + return -EUCLEAN; + } + + if (data_len && dir_type != BTRFS_FT_XATTR) { + dir_item_err(root, leaf, slot, + "dir item with invalid data len, have %u expect 0", + data_len); + return -EUCLEAN; + } + + total_size = sizeof(*di) + name_len + data_len; + + /* header and name/data should not cross item boundary */ + if (cur + total_size > item_size) { + dir_item_err(root, leaf, slot, + "dir item data crosses item boundary, have %u boundary %u", + cur + total_size, item_size); + return -EUCLEAN; + } + + /* + * Special check for XATTR/DIR_ITEM, as key->offset is name + * hash, should match its name + */ + if (key->type == BTRFS_DIR_ITEM_KEY || + key->type == BTRFS_XATTR_ITEM_KEY) { + read_extent_buffer(leaf, namebuf, + (unsigned long)(di + 1), name_len); + name_hash = btrfs_name_hash(namebuf, name_len); + if (key->offset != name_hash) { + dir_item_err(root, leaf, slot, + "name hash mismatch with key, have 0x%016x expect 0x%016llx", + name_hash, key->offset); + return -EUCLEAN; + } + } + cur += total_size; + di = (struct btrfs_dir_item *)((void *)di + total_size); + } + return 0; +} + /* * Common point to switch the item-specific validation. */ @@ -238,6 +374,11 @@ static int check_leaf_item(struct btrfs_root *root, case BTRFS_EXTENT_CSUM_KEY: ret = check_csum_item(root, leaf, key, slot); break; + case BTRFS_DIR_ITEM_KEY: + case BTRFS_DIR_INDEX_KEY: + case BTRFS_XATTR_ITEM_KEY: + ret = check_dir_item(root, leaf, key, slot); + break; } return ret; }