From patchwork Sat Nov 24 09:57:21 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pan Bian X-Patchwork-Id: 10696501 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 849BC14BD for ; Sat, 24 Nov 2018 09:57:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 732732ADD7 for ; Sat, 24 Nov 2018 09:57:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 660202ADE1; Sat, 24 Nov 2018 09:57:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 169FC2ADD7 for ; Sat, 24 Nov 2018 09:57:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726106AbeKXUpb (ORCPT ); Sat, 24 Nov 2018 15:45:31 -0500 Received: from m12-13.163.com ([220.181.12.13]:60059 "EHLO m12-13.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725940AbeKXUpb (ORCPT ); Sat, 24 Nov 2018 15:45:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=7J89eZ5fW8/oS2WhaN DIG5+D61MYEvp2nIuYqqeYPZo=; b=fmBaIyevuH37KFRuqYQlE+vZXg0cDhTzch E6T+fbPBnm8z5k02XPNduecKKA8HX7k6+IHZiDbBSDGnDB1YGGkQCMzr3lzC1BK1 X7t/umUNcP+CTI3IEl6U91MTU8tWsnUGv8S2wKHMnpDmCEIDn/uCWEW4Zqh+0/B8 MAcUAO/UU= Received: from bp.localdomain (unknown [106.120.213.96]) by smtp9 (Coremail) with SMTP id DcCowAA3zhaAIPlb6G5XBg--.53608S3; Sat, 24 Nov 2018 17:57:25 +0800 (CST) From: Pan Bian To: Andrew Morton , ernesto.mnd.fernandez@gmail.com Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Pan Bian Subject: [PATCH 1/1] hfsplus: do not free node before using Date: Sat, 24 Nov 2018 17:57:21 +0800 Message-Id: <1543053441-66942-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: DcCowAA3zhaAIPlb6G5XBg--.53608S3 X-Coremail-Antispam: 1Uf129KBjvdXoWrtr1DCw1xCFy5WF43tF48Xrb_yoWfGFc_Xa 1I9as7t3yrJFZ7JrZxArZ8t3sFgF4rG3s7Ww4xtF1Yk3yjyan8Jr1kZrnYkryfurWYqr15 JrWktry5Ga4UXjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IU0sYFJUUUUU== X-Originating-IP: [106.120.213.96] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/1tbiQAIJclSIYSB5fQAAsg Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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. Signed-off-by: Pan Bian --- fs/hfsplus/btree.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/hfsplus/btree.c b/fs/hfsplus/btree.c index 236efe5..66774f4 100644 --- a/fs/hfsplus/btree.c +++ b/fs/hfsplus/btree.c @@ -466,14 +466,15 @@ 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;