[PATCH for-next 10/10] io_uring: add an warn_once for poll_find

[Pavel Begunkov <asml.silence@gmail.com>]

io_poll_remove() expects poll_find() to search only for poll requests
and passes a flag for this. Just be a little bit extra cautious
considering lots of recent poll/cancellation changes and add a
WARN_ON_ONCE checking that we don't get an apoll'ed request.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 io_uring/poll.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/io_uring/poll.c b/io_uring/poll.c
index 9af6a34222a9..8f4fff76d3b4 100644
--- a/io_uring/poll.c
+++ b/io_uring/poll.c
@@ -827,6 +827,11 @@ int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
 	}
 
 found:
+	if (WARN_ON_ONCE(preq->opcode != IORING_OP_POLL_ADD)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
 	if (poll_update->update_events || poll_update->update_user_data) {
 		/* only mask one event flags, keep behavior flags */
 		if (poll_update->update_events) {
-- 
2.36.1