io_uring: fix timeout cancel return code

[ Upstream commit 1ee4160c73b2102a52bc97a4128a89c34821414f ]

When we cancel a timeout we should emit a sensible return code, like
-ECANCELED but not 0, otherwise it may trick users.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7b0ad1065e3bd1994722702bd0ba9e7bc9b0683b.1616696997.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 4ccf99c..0de27e7 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1489,7 +1489,7 @@ static void io_queue_async_work(struct io_kiocb *req)
                io_queue_linked_timeout(link);
 }
 
-static void io_kill_timeout(struct io_kiocb *req)
+static void io_kill_timeout(struct io_kiocb *req, int status)
 {
        struct io_timeout_data *io = req->async_data;
        int ret;
@@ -1499,7 +1499,7 @@ static void io_kill_timeout(struct io_kiocb *req)
                atomic_set(&req->ctx->cq_timeouts,
                        atomic_read(&req->ctx->cq_timeouts) + 1);
                list_del_init(&req->timeout.list);
-               io_cqring_fill_event(req, 0);
+               io_cqring_fill_event(req, status);
                io_put_req_deferred(req, 1);
        }
 }
@@ -1516,7 +1516,7 @@ static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
        spin_lock_irq(&ctx->completion_lock);
        list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
                if (io_match_task(req, tsk, files)) {
-                       io_kill_timeout(req);
+                       io_kill_timeout(req, -ECANCELED);
                        canceled++;
                }
        }
@@ -1568,7 +1568,7 @@ static void io_flush_timeouts(struct io_ring_ctx *ctx)
                        break;
 
                list_del_init(&req->timeout.list);
-               io_kill_timeout(req);
+               io_kill_timeout(req, 0);
        } while (!list_empty(&ctx->timeout_list));
 
        ctx->cq_last_tm_flush = seq;