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 55283C43441 for ; Sat, 24 Nov 2018 02:11:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 12EA020868 for ; Sat, 24 Nov 2018 02:11:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="XrQcL3eT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 12EA020868 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 S1729437AbeKXM6A (ORCPT ); Sat, 24 Nov 2018 07:58:00 -0500 Received: from m12-18.163.com ([220.181.12.18]:40781 "EHLO m12-18.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729268AbeKXM57 (ORCPT ); Sat, 24 Nov 2018 07:57:59 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=ZbW9rYi3Cz6z27YeA9 E1w9eoVVKUuxmORxUFqr6PC5A=; b=XrQcL3eTSM7uttLp7hSKMgSxWYvPE+kazm G6dRMiVdKL5KT/nNk6LecY3YPb99f11bSfNvHRfEwD/k2xhEbiVVG3S3ornKq8TS JPS/GytUdMCOdNKyWMPlMK0M9O1RSxf+RtGXuygvlYwrjlob4Wqor/bLYMQGx2Fm iubnIjbsw= Received: from bp.localdomain (unknown [106.120.213.96]) by smtp14 (Coremail) with SMTP id EsCowACn0zU4s_hb184VBg--.38107S3; Sat, 24 Nov 2018 10:11:16 +0800 (CST) From: Pan Bian To: Andrew Morton , ernesto.mnd.fernandez@gmail.com, Joe Perches Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Pan Bian Subject: [PATCH V2] hfs: do not free node before using Date: Sat, 24 Nov 2018 10:10:58 +0800 Message-Id: <1543025458-31592-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: EsCowACn0zU4s_hb184VBg--.38107S3 X-Coremail-Antispam: 1Uf129KBjvdXoWrtr1DCw1xCFy5WF43uFykXwb_yoWfZFb_JF 4xW3Wxt34rGFZ7Jrs3CrZYqw42gF4rGwnagw4xtFWak3yYyan5Jr1kZr9YyryfuFWYgrn8 J3yktryUGay7GjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IUnjFAJUUUUU== X-Originating-IP: [106.120.213.96] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/xtbBZwQJcletsGsCLAAAsX Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function hfs_bmap_free frees node via hfs_bnode_put(node). However, it then reads node->this when dumping error message on an error path, which may result in a use-after-free bug. This patch frees node only when it is never used. Fixes: a1185ffa2fc("HFS rewrite") Signed-off-by: Pan Bian --- V2: correct the commit information in Fixes --- fs/hfs/btree.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/hfs/btree.c b/fs/hfs/btree.c index 98b96ff..19017d2 100644 --- a/fs/hfs/btree.c +++ b/fs/hfs/btree.c @@ -338,13 +338,14 @@ void hfs_bmap_free(struct hfs_bnode *node) nidx -= len * 8; i = node->next; - hfs_bnode_put(node); if (!i) { /* panic */; pr_crit("unable to free bnode %u. bmap not found!\n", node->this); + hfs_bnode_put(node); return; } + hfs_bnode_put(node); node = hfs_bnode_find(tree, i); if (IS_ERR(node)) return; -- 2.7.4