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=-10.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 3A4D8C04EB8 for ; Tue, 4 Dec 2018 11:02:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F417F214E0 for ; Tue, 4 Dec 2018 11:02:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="PunfKxgU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F417F214E0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727676AbeLDLCm (ORCPT ); Tue, 4 Dec 2018 06:02:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:48702 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727645AbeLDLCh (ORCPT ); Tue, 4 Dec 2018 06:02:37 -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 C708E214DE; Tue, 4 Dec 2018 11:02:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543921356; bh=ruVAxiGuJ65EF5ZwxUgltLbCsYIIEWCQo6Fz8fa3H0k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PunfKxgU68n4Uy20K1Tb4otoKJfZ05AZI6vUhFzf8URwaK22EDDOdtlRLu3xhDSeL eWlk10AL39pYKf04fDEFYRdBmMgRhsvLx5wThRxiujeDkcsOHTozTEG84WiR+ZjUA6 dC3VNLA4HQiGUdcYYJORrXfkPz8UdLYdJIN/7OL0= 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 , Sasha Levin Subject: [PATCH 4.14 040/146] btrfs: tree-checker: Detect invalid and empty essential trees Date: Tue, 4 Dec 2018 11:48:46 +0100 Message-Id: <20181204103728.477493119@linuxfoundation.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181204103726.750894136@linuxfoundation.org> References: <20181204103726.750894136@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 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ 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 4.14: Pass root instead of fs_info to generic_err()] Signed-off-by: Ben Hutchings Signed-off-by: Sasha Levin --- fs/btrfs/tree-checker.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index cf9b10a07134..31756bac75b4 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -456,9 +456,22 @@ static int check_leaf(struct btrfs_root *root, struct extent_buffer *leaf, * 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; -- 2.17.1