On Tue, Dec 29, 2020 at 04:35:49AM +0000, Pavel Begunkov wrote:
commit dfea9fce29fda6f2f91161677e0e0d9b671bc099 upstream.
The purpose of io_uring_cancel_files() is to wait for all requests matching ->files to go/be cancelled. We should first drop files of a request in io_req_drop_files() and only then make it undiscoverable for io_uring_cancel_files.
First drop, then delete from list. It's ok to leave req->id->files dangling, because it's not dereferenced by cancellation code, only compared against. It would potentially go to sleep and be awaken by following in io_req_drop_files() wake_up().
Fixes: 0f2122045b946 ("io_uring: don't rely on weak ->files references") Cc: stable@vger.kernel.org # 5.5+ Signed-off-by: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk
fs/io_uring.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
Now applied, thanks.
greg k-h