Congress has just voted to hold AG Barr in contempt of Congress for failing to comply with their subpoena of the unredacted Mueller report?

I have heard conflicting stories about the legality of this proceeding. I have heard that AG Barr can not be ordered to break federal law by Congress, and that by providing Congress with unredacted materials relating to ongoing Grand Jury information Barr would be breaking the law.

I have heard that ALL information in the Mueller report is available to Congress except for protected Grand Jury information.