Hi Syed,
I assume by "smart objects" you are referring to Portable Fragment Bookmarks. A couple points:
1) If you only want users to see smart objects they have created, then the application should use the concept of Fragment Bookmarks for this requirement instead of Portable Fragment Bookmarks, as Fragment Bookmarks are user-specific. However, I'm not sure if regular Fragment Bookmarks can be loaded into a Fragment Gallery but you could try;
2) Smart Objects are intended to be shared across multiple users. If you want to restrict access of Smart Objects to specific groups of users then in the CMC Bookmark Folder Administration you should apply the appropriate security to the bookmark folders as shown below:
Regards,
Mustafa.