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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 DCEA3C5CFE7 for ; Tue, 10 Jul 2018 18:35:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A7FC8208E8 for ; Tue, 10 Jul 2018 18:35:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A7FC8208E8 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 S2389712AbeGJSf5 (ORCPT ); Tue, 10 Jul 2018 14:35:57 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:48392 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389693AbeGJSf4 (ORCPT ); Tue, 10 Jul 2018 14:35:56 -0400 Received: from localhost (LFbn-1-12247-202.w90-92.abo.wanadoo.fr [90.92.61.202]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 3C412E78; Tue, 10 Jul 2018 18:35:43 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Theodore Tso , stable@kernel.org Subject: [PATCH 4.17 36/56] ext4: never move the system.data xattr out of the inode body Date: Tue, 10 Jul 2018 20:25:18 +0200 Message-Id: <20180710182505.329735153@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180710182503.544433950@linuxfoundation.org> References: <20180710182503.544433950@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Theodore Ts'o commit 8cdb5240ec5928b20490a2bb34cb87e9a5f40226 upstream. When expanding the extra isize space, we must never move the system.data xattr out of the inode body. For performance reasons, it doesn't make any sense, and the inline data implementation assumes that system.data xattr is never in the external xattr block. This addresses CVE-2018-10880 https://bugzilla.kernel.org/show_bug.cgi?id=200005 Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman --- fs/ext4/xattr.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -2657,6 +2657,11 @@ static int ext4_xattr_make_inode_space(h last = IFIRST(header); /* Find the entry best suited to be pushed into EA block */ for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { + /* never move system.data out of the inode */ + if ((last->e_name_len == 4) && + (last->e_name_index == EXT4_XATTR_INDEX_SYSTEM) && + !memcmp(last->e_name, "data", 4)) + continue; total_size = EXT4_XATTR_LEN(last->e_name_len); if (!last->e_value_inum) total_size += EXT4_XATTR_SIZE(