[PATCH] io_uring/net: avoid sending -ECONNABORTED on repeated connection requests

[Jens Axboe <axboe@kernel.dk>]

Since io_uring does nonblocking connect requests, if we do two repeated
ones without having a listener, the second will get -ECONNABORTED rather
than the expected -ECONNREFUSED. Treat -ECONNABORTED like a normal retry
condition if we're nonblocking, if we haven't already seen it.

Cc: stable@vger.kernel.org
Fixes: 3fb1bd688172 ("io_uring/net: handle -EINPROGRESS correct for IORING_OP_CONNECT")
Link: https://github.com/axboe/liburing/issues/828
Signed-off-by: Jens Axboe <axboe@kernel.dk>

---

diff --git a/io_uring/net.c b/io_uring/net.c
index b7f190ca528e..4040cf093318 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -47,6 +47,7 @@ struct io_connect {
 	struct sockaddr __user		*addr;
 	int				addr_len;
 	bool				in_progress;
+	bool				seen_econnaborted;
 };
 
 struct io_sr_msg {
@@ -1424,7 +1425,7 @@ int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 
 	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
 	conn->addr_len =  READ_ONCE(sqe->addr2);
-	conn->in_progress = false;
+	conn->in_progress = conn->seen_econnaborted = false;
 	return 0;
 }
 
@@ -1461,18 +1462,24 @@ int io_connect(struct io_kiocb *req, unsigned int issue_flags)
 
 	ret = __sys_connect_file(req->file, &io->address,
 					connect->addr_len, file_flags);
-	if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
+	if ((ret == -EAGAIN || ret == -EINPROGRESS || ret == -ECONNABORTED)
+	    && force_nonblock) {
 		if (ret == -EINPROGRESS) {
 			connect->in_progress = true;
-		} else {
-			if (req_has_async_data(req))
-				return -EAGAIN;
-			if (io_alloc_async_data(req)) {
-				ret = -ENOMEM;
+			return -EAGAIN;
+		}
+		if (ret == -ECONNABORTED) {
+			if (connect->seen_econnaborted)
 				goto out;
-			}
-			memcpy(req->async_data, &__io, sizeof(__io));
+			connect->seen_econnaborted = true;
+		}
+		if (req_has_async_data(req))
+			return -EAGAIN;
+		if (io_alloc_async_data(req)) {
+			ret = -ENOMEM;
+			goto out;
 		}
+		memcpy(req->async_data, &__io, sizeof(__io));
 		return -EAGAIN;
 	}
 	if (ret == -ERESTARTSYS)

-- 
Jens Axboe