io_uring: fix spurious fput in registered ring path

Fix an issue with io_uring_ctx_get_file() not gating fput() on whether
or not the file descriptor is a registered/direct one or not.

Fixes: c5e9f6a ("io_uring: unify getting ctx from passed in file descriptor")
Reviewed-by: Gabriel Krisman Bertazi <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

Author: axboe

io_uring/io_uring.c

@@ -2575,7 +2575,8 @@ struct file *io_uring_ctx_get_file(unsigned int fd, bool registered)
 		return ERR_PTR(-EBADF);
 	if (io_is_uring_fops(file))
 		return file;
-	fput(file);
+	if (!registered)
+		fput(file);
 	return ERR_PTR(-EOPNOTSUPP);
 }