From: Jens Axboe <axboe@xxxxxxxxx> commit 36703247d5f52a679df9da51192b6950fe81689f upstream. Daniel reports that when testing an http server that uses io_uring to poll for incoming connections, sometimes it hard crashes. This is due to an uninitialized list member for the io_uring request. Normally this doesn't trigger and none of the test cases caught it. Reported-by: Daniel Kozak <kozzi11@xxxxxxxxx> Tested-by: Daniel Kozak <kozzi11@xxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/io_uring.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1489,6 +1489,8 @@ static int io_poll_add(struct io_kiocb * INIT_LIST_HEAD(&poll->wait.entry); init_waitqueue_func_entry(&poll->wait, io_poll_wake); + INIT_LIST_HEAD(&req->list); + mask = vfs_poll(poll->file, &ipt.pt) & poll->events; spin_lock_irq(&ctx->completion_lock);
