I added my questions as a comment on the post:
Please clarify: Which operating system and version do you use? Which permission errors are you referring to? Do you need the individual sizes or the total size of these files? What have you tried, and where did it fail?
Some of these questions are there for hours in other comments, but still OP has failed to address them – the post actually seems abandoned. As it stands, the question does qualify for both “unclear” and “too broad”: There is not even a clear question, see the extended comment discussion resulting from this fact.
As for the downvotes, people are generally free to do that at will, but the guideline (see mouseover) says:
This question does not show any research effort; it is unclear or not useful (click again to undo)
As it stands, the first two of these three objectively match, while the third may subjectively.