[PATCH 1/1] io_uring: fix multishots with selected buffers

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

We do io_kbuf_recycle() when arming a poll but every iteration of a
multishot can grab more buffers, which is why we need to flush the kbuf
ring state before continuing with waiting.

Cc: stable@vger.kernel.org
Fixes: b3fdea6ecb55c ("io_uring: multishot recv")
Reported-by: Muhammad Ramdhan <ramdhan@starlabs.sg>
Reported-by: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Reported-by: Jacob Soo <jacob.soo@starlabs.sg>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 io_uring/poll.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/io_uring/poll.c b/io_uring/poll.c
index cc01c40b43d31..f12a857bb8555 100644
--- a/io_uring/poll.c
+++ b/io_uring/poll.c
@@ -315,8 +315,10 @@ void io_poll_task_func(struct io_kiocb *req, struct io_tw_state *ts)
 
 	ret = io_poll_check_events(req, ts);
 	if (ret == IOU_POLL_NO_ACTION) {
+		io_kbuf_recycle(req, 0);
 		return;
 	} else if (ret == IOU_POLL_REQUEUE) {
+		io_kbuf_recycle(req, 0);
 		__io_poll_execute(req, 0);
 		return;
 	}
-- 
2.47.1