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=-9.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 E9B69C43441 for ; Tue, 13 Nov 2018 05:51:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A623E2251B for ; Tue, 13 Nov 2018 05:51:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="gs5wYNjI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A623E2251B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.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 S1732169AbeKMPrr (ORCPT ); Tue, 13 Nov 2018 10:47:47 -0500 Received: from mail.kernel.org ([198.145.29.99]:33608 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732103AbeKMPrp (ORCPT ); Tue, 13 Nov 2018 10:47:45 -0500 Received: from sasha-vm.mshome.net (unknown [64.114.255.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 37A6522510; Tue, 13 Nov 2018 05:51:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542088278; bh=aZ44YYUIpSqiy+YcR9z+AlOWsiug84F1Zyu+IX9GZCs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gs5wYNjIEdv/HHQm8udimKguQKk/T2ridFP8BzJm7GbLJxDQ8ngy92BHerqR1rKz6 cClCPTak+Ah3SjgWiTNRSo+7xAeZw8YNYMvEcqcZNXfvRzeWEjKghILOP8xeF8+7Ii RbZgY+X7/5HOCzOqCxMwpfharZHnyGY+8h20uevQ= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Ernesto=20A=2E=20Fern=C3=A1ndez?= , Christoph Hellwig , Andrew Morton , Linus Torvalds , Sasha Levin , linux-fsdevel@vger.kernel.org Subject: [PATCH AUTOSEL 4.18 14/39] hfs: prevent btree data loss on root split Date: Tue, 13 Nov 2018 00:50:28 -0500 Message-Id: <20181113055053.78352-14-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181113055053.78352-1-sashal@kernel.org> References: <20181113055053.78352-1-sashal@kernel.org> 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 From: Ernesto A. Fernández [ Upstream commit d057c036672f33d43a5f7344acbb08cf3a8a0c09 ] This bug is triggered whenever hfs_brec_update_parent() needs to split the root node. The height of the btree is not increased, which leaves the new node orphaned and its records lost. It is not possible for this to happen on a valid hfs filesystem because the index nodes have fixed length keys. For reasons I ignore, the hfs module does have support for a number of hfsplus features. A corrupt btree header may report variable length keys and trigger this bug, so it's better to fix it. Link: http://lkml.kernel.org/r/9750b1415685c4adca10766895f6d5ef12babdb0.1535682463.git.ernesto.mnd.fernandez@gmail.com Signed-off-by: Ernesto A. Fernández Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- fs/hfs/brec.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/hfs/brec.c b/fs/hfs/brec.c index 9a8772465a90..da25c49203cc 100644 --- a/fs/hfs/brec.c +++ b/fs/hfs/brec.c @@ -425,6 +425,10 @@ static int hfs_brec_update_parent(struct hfs_find_data *fd) if (new_node) { __be32 cnid; + if (!new_node->parent) { + hfs_btree_inc_height(tree); + new_node->parent = tree->root; + } fd->bnode = hfs_bnode_find(tree, new_node->parent); /* create index key and entry */ hfs_bnode_read_key(new_node, fd->search_key, 14); -- 2.17.1