My cousin tried updating from 10.9 to 10.10 and it keeps looping through the installation. When I run a Disk Repair it says the disk cannot be repaired. I can mount the disk in Ubuntu 14.10 LIVE but I cannot get permissions to access the files any further; I'm not the owner. I am unable to figure out how to mount the drive with the ability to edit the contents. (HFS+ filesystem)
I have the MacBook Pro and a USB hard drive that are both in the HFS+ filesystem. I desperately need to recover the files from the Mac onto the USB hard drive before proceeding with troubleshooting the internal hard drive of the Mac.