[PATCH 1/1] io_uring: fix mshot read defer taskrun cqe posting

[Pavel Begunkov <asml.silence@xxxxxxxxx>]

We can't post CQEs from io-wq with DEFER_TASKRUN set, normal completions
are handled but aux should be explicitly disallowed by opcode handlers.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: fc68fcda04910 ("io_uring/rw: add support for IORING_OP_READ_MULTISHOT")
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
 io_uring/rw.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/io_uring/rw.c b/io_uring/rw.c
index d5e79d9bdc71..8756e367acd9 100644
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -932,6 +932,8 @@ int io_read_mshot(struct io_kiocb *req, unsigned int issue_flags)
 	 */
 	if (!file_can_poll(req->file))
 		return -EBADFD;
+	if (issue_flags & IO_URING_F_IOWQ)
+		return -EAGAIN;
 
 	ret = __io_read(req, issue_flags);
 
-- 
2.43.0