From patchwork Thu Oct 29 09:31:44 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhaolei X-Patchwork-Id: 7517751 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id D0988BEEA4 for ; Thu, 29 Oct 2015 09:34:01 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id DC72820772 for ; Thu, 29 Oct 2015 09:34:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E945D208A1 for ; Thu, 29 Oct 2015 09:33:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756456AbbJ2Jdn (ORCPT ); Thu, 29 Oct 2015 05:33:43 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:5639 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752375AbbJ2Jdj (ORCPT ); Thu, 29 Oct 2015 05:33:39 -0400 X-IronPort-AV: E=Sophos;i="5.15,520,1432569600"; d="scan'208";a="102430434" Received: from unknown (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 29 Oct 2015 17:35:50 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id t9T9X3Y1015819 for ; Thu, 29 Oct 2015 17:33:03 +0800 Received: from localhost.localdomain (10.167.226.114) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server id 14.3.181.6; Thu, 29 Oct 2015 17:33:36 +0800 From: Zhao Lei To: CC: Zhao Lei Subject: [PATCH 2/6] btrfs-progs: Fix negative eb's ref_cnt in btrfs-calc-size Date: Thu, 29 Oct 2015 17:31:44 +0800 Message-ID: <8e1a2c10dd36c558d8f0b4818f48bca5bb780b9b.1446111097.git.zhaolei@cn.fujitsu.com> X-Mailer: git-send-email 1.8.5.1 In-Reply-To: References: MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP btrfs-calc-size show following warning: # btrfs-calc-size /dev/sda6 Calculating size of root tree ... extent_io.c:582: free_extent_buffer: Assertion `eb->refs < 0` failed. ./btrfs-calc-size[0x41d642] ./btrfs-calc-size(free_extent_buffer+0x70)[0x41e1c1] ./btrfs-calc-size(btrfs_free_fs_root+0x11)[0x40e1e8] ./btrfs-calc-size[0x40e215] ./btrfs-calc-size(rb_free_nodes+0x1d)[0x4326fe] ./btrfs-calc-size(close_ctree+0x3f3)[0x40f9ea] ./btrfs-calc-size(main+0x200)[0x431b4e] /lib64/libc.so.6(__libc_start_main+0xf5)[0x3858621d65] ./btrfs-calc-size[0x407009] Reason: path in calc_root_size() is only used to save node data, it don't hold ref_cnt for each eb in. Using btrfs_free_path() to free path will reduce these eb again, and cause many problems, as negative ref_cnt or invalid memory access. Signed-off-by: Zhao Lei --- btrfs-calc-size.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/btrfs-calc-size.c b/btrfs-calc-size.c index 17d44ae..b84cda9 100644 --- a/btrfs-calc-size.c +++ b/btrfs-calc-size.c @@ -417,7 +417,14 @@ out: free(seek); } - btrfs_free_path(path); + /* + * We only use path to save node data in iterating, + * without holding eb's ref_cnt in path. + * Don't use btrfs_free_path() here, it will free these + * eb again, and cause many problems, as negative ref_cnt + * or invalid memory access. + */ + free(path); return ret; }