Files
linux/fs/ocfs2
Dmitry Monakhov 77b14d6ebc quota: Check that quota is not dirty before release
commit df4bb5d128 upstream.

There is a race window where quota was redirted once we drop dq_list_lock inside dqput(),
but before we grab dquot->dq_lock inside dquot_release()

TASK1                                                       TASK2 (chowner)
->dqput()
  we_slept:
    spin_lock(&dq_list_lock)
    if (dquot_dirty(dquot)) {
          spin_unlock(&dq_list_lock);
          dquot->dq_sb->dq_op->write_dquot(dquot);
          goto we_slept
    if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
          spin_unlock(&dq_list_lock);
          dquot->dq_sb->dq_op->release_dquot(dquot);
                                                            dqget()
							    mark_dquot_dirty()
							    dqput()
          goto we_slept;
        }
So dquot dirty quota will be released by TASK1, but on next we_sleept loop
we detect this and call ->write_dquot() for it.
XFSTEST: 440a80d4cb

Link: https://lore.kernel.org/r/20191031103920.3919-2-dmonakhov@openvz.org
CC: stable@vger.kernel.org
Signed-off-by: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-17 20:35:17 +01:00
..
2019-02-12 19:47:18 +01:00
2017-09-06 17:27:24 -07:00
2018-08-17 16:20:27 -07:00
2019-12-01 09:17:36 +01:00
2018-01-31 17:18:35 -08:00
2018-01-31 17:18:35 -08:00
2018-08-17 16:20:27 -07:00
2019-02-12 19:47:18 +01:00
2018-06-12 16:19:22 -07:00