From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64E95C43387 for ; Tue, 15 Jan 2019 16:37:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 324E020868 for ; Tue, 15 Jan 2019 16:37:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547570262; bh=QcXfen9aQgYi15kJQqv0CwyppH3+38GS55F5Tu+IhPI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QJEUGPByhOXKowOkLMvWVcfuPLMHh+NBkACqk24KNtbvHnyG/zBlw4v2bNOa1Bj9j OCLZCV2936QwzMSOeGtmjKx+XD8Rm6EFbkHY4Z35LXv3cHJthn0Qc5gumU+EyThsa3 DxWibXLRGWemZvDcU4oWhmNTgbzYccc/4jZszlo8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731905AbfAOQhk (ORCPT ); Tue, 15 Jan 2019 11:37:40 -0500 Received: from mail.kernel.org ([198.145.29.99]:53234 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731885AbfAOQhh (ORCPT ); Tue, 15 Jan 2019 11:37:37 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B287020873; Tue, 15 Jan 2019 16:37:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547570257; bh=QcXfen9aQgYi15kJQqv0CwyppH3+38GS55F5Tu+IhPI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eSFgmIG73Bx/g0hgbSiwbCK6nLAAUhtqrZMBe8xiE03B2/i1EiQxJh5jPCan92f6g 5ggFAVRiThuw6Yxm6hh+ref0sWTLJ++3SCNA2Ub0OKNBZrUFH52EotSrE7psRHVVdN T7aVOLQ/KgvsBCaEVVt2VJpCAnvzXGRlI3R3XcQY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xu Wen , Qu Wenruo , Gu Jinxiang , David Sterba , Ben Hutchings Subject: [PATCH 4.4 27/51] btrfs: tree-checker: Detect invalid and empty essential trees Date: Tue, 15 Jan 2019 17:35:23 +0100 Message-Id: <20190115154850.539778691@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190115154846.928796000@linuxfoundation.org> References: <20190115154846.928796000@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Qu Wenruo commit ba480dd4db9f1798541eb2d1c423fc95feee8d36 upstream. A crafted image has empty root tree block, which will later cause NULL pointer dereference. The following trees should never be empty: 1) Tree root Must contain at least root items for extent tree, device tree and fs tree 2) Chunk tree Or we can't even bootstrap as it contains the mapping. 3) Fs tree At least inode item for top level inode (.). 4) Device tree Dev extents for chunks 5) Extent tree Must have corresponding extent for each chunk. If any of them is empty, we are sure the fs is corrupted and no need to mount it. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199847 Reported-by: Xu Wen Signed-off-by: Qu Wenruo Tested-by: Gu Jinxiang Reviewed-by: David Sterba Signed-off-by: David Sterba [bwh: Backported to 4.4: Pass root instead of fs_info to generic_err()] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/tree-checker.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -456,9 +456,22 @@ static int check_leaf(struct btrfs_root * skip this check for relocation trees. */ if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) { + u64 owner = btrfs_header_owner(leaf); struct btrfs_root *check_root; - key.objectid = btrfs_header_owner(leaf); + /* These trees must never be empty */ + if (owner == BTRFS_ROOT_TREE_OBJECTID || + owner == BTRFS_CHUNK_TREE_OBJECTID || + owner == BTRFS_EXTENT_TREE_OBJECTID || + owner == BTRFS_DEV_TREE_OBJECTID || + owner == BTRFS_FS_TREE_OBJECTID || + owner == BTRFS_DATA_RELOC_TREE_OBJECTID) { + generic_err(root, leaf, 0, + "invalid root, root %llu must never be empty", + owner); + return -EUCLEAN; + } + key.objectid = owner; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = (u64)-1;