diff options
| author | Alexander Aring <aahringo@redhat.com> | 2022-08-15 15:43:14 -0400 |
|---|---|---|
| committer | David Teigland <teigland@redhat.com> | 2022-08-23 14:37:14 -0500 |
| commit | eef6ec9bf390e836a6c4029f3620fe49528aa1fe (patch) | |
| tree | 58944a50286630dcff9c3122552b9fe556d19e28 /fs/dlm | |
| parent | 30ea3257e8766027c4d8d609dcbd256ff9a76073 (diff) | |
fs: dlm: fix race between test_bit() and queue_work()
This patch fixes a race by using ls_cb_mutex around the bit
operations and conditional code blocks for LSFL_CB_DELAY.
The function dlm_callback_stop() expects to stop all callbacks and
flush all currently queued onces. The set_bit() is not enough because
there can still be queue_work() after the workqueue was flushed.
To avoid queue_work() after set_bit(), surround both by ls_cb_mutex.
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Diffstat (limited to 'fs/dlm')
| -rw-r--r-- | fs/dlm/ast.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/dlm/ast.c b/fs/dlm/ast.c index 19ef136f9e4f..a44cc42b6317 100644 --- a/fs/dlm/ast.c +++ b/fs/dlm/ast.c @@ -200,13 +200,13 @@ void dlm_add_cb(struct dlm_lkb *lkb, uint32_t flags, int mode, int status, if (!prev_seq) { kref_get(&lkb->lkb_ref); + mutex_lock(&ls->ls_cb_mutex); if (test_bit(LSFL_CB_DELAY, &ls->ls_flags)) { - mutex_lock(&ls->ls_cb_mutex); list_add(&lkb->lkb_cb_list, &ls->ls_cb_delay); - mutex_unlock(&ls->ls_cb_mutex); } else { queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work); } + mutex_unlock(&ls->ls_cb_mutex); } out: mutex_unlock(&lkb->lkb_cb_mutex); @@ -288,7 +288,9 @@ void dlm_callback_stop(struct dlm_ls *ls) void dlm_callback_suspend(struct dlm_ls *ls) { + mutex_lock(&ls->ls_cb_mutex); set_bit(LSFL_CB_DELAY, &ls->ls_flags); + mutex_unlock(&ls->ls_cb_mutex); if (ls->ls_callback_wq) flush_workqueue(ls->ls_callback_wq); |