"Baidu Yun" is an online file locker (like Dropbox) with a generous free quota. You can create a shareable link for a file with a single click. Why would you think someone at Baidu would have knowledge of a particular file a user shared on that service?
Separately, you bring up Baidu's "involvement" in the DDoS attack on GitHub. I remember reading that this was achieved using a man-in-the-middle attack on customers of Baidu's analytics product, which would not need Baidu's cooperation: http://www.netresec.com/?page=Blog&month=2015-03&post=China%...
Separately, you bring up Baidu's "involvement" in the DDoS attack on GitHub. I remember reading that this was achieved using a man-in-the-middle attack on customers of Baidu's analytics product, which would not need Baidu's cooperation: http://www.netresec.com/?page=Blog&month=2015-03&post=China%...