From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755569AbaD1BdL (ORCPT ); Sun, 27 Apr 2014 21:33:11 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42853 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752470AbaD1B3U (ORCPT ); Sun, 27 Apr 2014 21:29:20 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Jan Kara" , "Jeff Mahoney" Date: Mon, 28 Apr 2014 02:11:22 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 72/94] reiserfs: fix race in readdir In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.58-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Mahoney commit 01d8885785a60ae8f4c37b0ed75bdc96d0fc6a44 upstream. jdm-20004 reiserfs_delete_xattrs: Couldn't delete all xattrs (-2) The -ENOENT is due to readdir calling dir_emit on the same entry twice. If the dir_emit callback sleeps and the tree is changed underneath us, we won't be able to trust deh_offset(deh) anymore. We need to save next_pos before we might sleep so we can find the next entry. Signed-off-by: Jeff Mahoney Signed-off-by: Jan Kara Signed-off-by: Ben Hutchings --- fs/reiserfs/dir.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/fs/reiserfs/dir.c +++ b/fs/reiserfs/dir.c @@ -128,6 +128,7 @@ int reiserfs_readdir_dentry(struct dentr char *d_name; off_t d_off; ino_t d_ino; + loff_t cur_pos = deh_offset(deh); if (!de_visible(deh)) /* it is hidden entry */ @@ -200,8 +201,9 @@ int reiserfs_readdir_dentry(struct dentr if (local_buf != small_buf) { kfree(local_buf); } - // next entry should be looked for with such offset - next_pos = deh_offset(deh) + 1; + + /* deh_offset(deh) may be invalid now. */ + next_pos = cur_pos + 1; if (item_moved(&tmp_ih, &path_to_entry)) { goto research;