From: Jens Axboe axboe@kernel.dk
commit e47498afeca9a0c6d07eeeacc46d563555a3f677 upstream.
There's a small race here where the task_work could finish and drop the worker itself, so that by the time that task_work_add() returns with a successful addition we've already put the worker.
The worker callbacks clear this bit themselves, so we don't actually need to manually clear it in the caller. Get rid of it.
Reported-by: syzbot+b60c982cb0efc5e05a47@syzkaller.appspotmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/io-wq.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
--- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -359,10 +359,8 @@ static bool io_queue_worker_create(struc
init_task_work(&worker->create_work, func); worker->create_index = acct->index; - if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL)) { - clear_bit_unlock(0, &worker->create_state); + if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL)) return true; - } clear_bit_unlock(0, &worker->create_state); fail_release: io_worker_release(worker);