[PATCH v2] io_uring/net: clear msg_controllen on partial sendmsg retry

From: Jens Axboe <axboe@kernel.dk>
To: io-uring <io-uring@vger.kernel.org>
Cc: Stefan Metzmacher <metze@samba.org>
Subject: [PATCH v2] io_uring/net: clear msg_controllen on partial sendmsg retry
Date: Tue, 20 Jun 2023 07:19:47 -0600	[thread overview]
Message-ID: <312cc2b7-8229-c167-e230-bc1d7d0ed61b@kernel.dk> (raw)

If we have cmsg attached AND we transferred partial data at least, clear
msg_controllen on retry so we don't attempt to send that again.

Cc: stable@vger.kernel.org # 5.10+
Fixes: cac9e4418f4c ("io_uring/net: save msghdr->msg_control for retries")
Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

v2: clear msg_control as well

 io_uring/net.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/io_uring/net.c b/io_uring/net.c
index 51b0f7fbb4f5..c0924ab1ea11 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -326,6 +326,8 @@ int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
 			return io_setup_async_msg(req, kmsg, issue_flags);
 		if (ret > 0 && io_net_retry(sock, flags)) {
+			kmsg->msg.msg_controllen = 0;
+			kmsg->msg.msg_control = NULL;
 			sr->done_io += ret;
 			req->flags |= REQ_F_PARTIAL_IO;
 			return io_setup_async_msg(req, kmsg, issue_flags);
-- 
2.39.2

-- 
Jens Axboe

