From patchwork Sat Nov 24 02:10:58 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pan Bian X-Patchwork-Id: 10696407 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 C92F416B1 for ; Sat, 24 Nov 2018 02:11:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B23502B9A2 for ; Sat, 24 Nov 2018 02:11:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A618F2B9B4; Sat, 24 Nov 2018 02:11:25 +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 61C192B9A2 for ; Sat, 24 Nov 2018 02:11:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729344AbeKXM6A (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-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. 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;