From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Mahoney Subject: [PATCH v2] reiserfs: fix race in readdir Date: Wed, 02 Apr 2014 14:40:26 -0400 Message-ID: <533C599A.9010503@suse.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: Sender: reiserfs-devel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: reiserfs-devel Cc: Jan Kara 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 --- fs/reiserfs/dir.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/fs/reiserfs/dir.c +++ b/fs/reiserfs/dir.c @@ -125,6 +125,7 @@ int reiserfs_readdir_inode(struct inode int d_reclen; char *d_name; ino_t d_ino; + loff_t cur_pos = deh_offset(deh); if (!de_visible(deh)) /* it is hidden entry */ @@ -196,8 +197,9 @@ int reiserfs_readdir_inode(struct inode 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)) { set_cpu_key_k_offset(&pos_key, -- Jeff Mahoney SUSE Labs