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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,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 B89CEC43610 for ; Mon, 26 Nov 2018 03:21:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7DE5D20865 for ; Mon, 26 Nov 2018 03:21:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="T0SqVDwu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7DE5D20865 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=163.com 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 S1726208AbeKZOO0 (ORCPT ); Mon, 26 Nov 2018 09:14:26 -0500 Received: from m12-17.163.com ([220.181.12.17]:35171 "EHLO m12-17.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726116AbeKZOOZ (ORCPT ); Mon, 26 Nov 2018 09:14:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=7A4ihKGl+zCslg/+6W 5OvV8mY9+t1E/X9U+NulVAZjY=; b=T0SqVDwur0Y7nR0XQaSQVs1LMTtWLqpolT yCnIgiHJvIYVNfN3/CFwAg2lode+P4G2jRNe0a0SD/zAiL8RTfuBW20b5oDBtu4x s0e+buhRxgau9qdPGy2ee0OoEReHTsuABTLIr+RaEZqMlRQA8AzmVJppf0/PE9cG ltDQWkovY= Received: from bp.localdomain (unknown [106.120.213.96]) by smtp13 (Coremail) with SMTP id EcCowABXI2WiZvtbfg2eBg--.13072S3; Mon, 26 Nov 2018 11:21:08 +0800 (CST) From: Pan Bian To: "Theodore Ts\'o" , Andreas Dilger Cc: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Pan Bian Subject: [PATCH] ext4: fix possible use after free in ext4_quota_enable Date: Mon, 26 Nov 2018 11:21:06 +0800 Message-Id: <1543202466-68277-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: EcCowABXI2WiZvtbfg2eBg--.13072S3 X-Coremail-Antispam: 1Uf129KBjvdXoW7Xr4rKryfWryrAw4rAr4kCrg_yoWfZFg_Xa 1xKF4Iv3sxXrn3KayvkFW3tr1v9F48uF45GF9Yqw4fu34Y9Fs8JFyDArnrAwn3W3y3t3s8 Arn2yF15XFW8ujkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IU0vzuJUUUUU== X-Originating-IP: [106.120.213.96] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/xtbBZAgLclQHCq5JKQAAsC Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function frees qf_inode via iput but then pass qf_inode to lockdep_set_quota_inode on the failure path. This may result in a use-after-free bug. The patch frees df_inode only when it is never used. Signed-off-by: Pan Bian Fixes: daf647d2dd5("ext4: add lockdep annotations for i_data_sem") --- fs/ext4/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 53ff6c2..35689eb 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5690,9 +5690,9 @@ static int ext4_quota_enable(struct super_block *sb, int type, int format_id, qf_inode->i_flags |= S_NOQUOTA; lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA); err = dquot_enable(qf_inode, type, format_id, flags); - iput(qf_inode); if (err) lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL); + iput(qf_inode); return err; } -- 2.7.4