io_uring: fix async accept on O_NONBLOCK sockets

commit a73825ba70 upstream.

Do not set REQ_F_NOWAIT if the socket is non blocking. When enabled this
causes the accept to immediately post a CQE with EAGAIN, which means you
cannot perform an accept SQE on a NONBLOCK socket asynchronously.

By removing the flag if there is no pending accept then poll is armed as
usual and when a connection comes in the CQE is posted.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220324143435.2875844-1-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Dylan Yudaken 2023-01-21 09:13:12 -07:00 committed by Justin Hammond
parent 561ffa127a
commit 24830fa51e

View file

@ -5272,9 +5272,6 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
struct file *file;
int ret, fd;
if (req->file->f_flags & O_NONBLOCK)
req->flags |= REQ_F_NOWAIT;
if (!fixed) {
fd = __get_unused_fd_flags(accept->flags, accept->nofile);
if (unlikely(fd < 0))
@ -5286,6 +5283,8 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
if (!fixed)
put_unused_fd(fd);
ret = PTR_ERR(file);
/* safe to retry */
req->flags |= REQ_F_PARTIAL_IO;
if (ret == -EAGAIN && force_nonblock)
return -EAGAIN;
if (ret == -ERESTARTSYS)