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=-5.8 required=3.0 tests=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 E513DC43382 for ; Thu, 27 Sep 2018 09:24:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A1DFF2156B for ; Thu, 27 Sep 2018 09:24:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A1DFF2156B 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 S1728928AbeI0PmI (ORCPT ); Thu, 27 Sep 2018 11:42:08 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:56714 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727411AbeI0PmH (ORCPT ); Thu, 27 Sep 2018 11:42:07 -0400 Received: from localhost (ip-213-127-77-73.ip.prioritytelecom.net [213.127.77.73]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id E55F5111C; Thu, 27 Sep 2018 09:24:46 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Theodore Tso , Wen Xu Subject: [PATCH 4.14 51/64] ext4: check to make sure the rename(2)s destination is not freed Date: Thu, 27 Sep 2018 11:04:08 +0200 Message-Id: <20180927090257.098102014@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20180927090249.801943776@linuxfoundation.org> References: <20180927090249.801943776@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review 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. ------------------ From: Theodore Ts'o commit b50282f3241acee880514212d88b6049fb5039c8 upstream. If the destination of the rename(2) system call exists, the inode's link count (i_nlinks) must be non-zero. If it is, the inode can end up on the orphan list prematurely, leading to all sorts of hilarity, including a use-after-free. https://bugzilla.kernel.org/show_bug.cgi?id=200931 Signed-off-by: Theodore Ts'o Reported-by: Wen Xu Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- fs/ext4/namei.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -3514,6 +3514,12 @@ static int ext4_rename(struct inode *old int credits; u8 old_file_type; + if (new.inode && new.inode->i_nlink == 0) { + EXT4_ERROR_INODE(new.inode, + "target of rename is already freed"); + return -EFSCORRUPTED; + } + if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) && (!projid_eq(EXT4_I(new_dir)->i_projid, EXT4_I(old_dentry->d_inode)->i_projid)))