MacOS – Changed the mod for ~/.. directory by mistake, made it 744, can’t boot anymore

bootmacospermissionterminal

I ran the following command by mistake:

sudo chmod 744 ~/..

and I can't boot my macbook anymore, it freezes with the brown screen and ajax-style spin. What should I do to make it work normally again?

I tried:

a) Disk utility (repair permissions) – didn't help
b) resetpassword -> reset ACL and permissions for home directory – didn't help.

I booted in the recovery mode, opened the terminal and went to "/Volumes/Macintosh HD". Yes, this was the disk (or should I say "path") I changed the permissions for.

How do I restore them now? And what are they were?

UPDATE:

I was able to restore it by going to the terminal in recovery mode and performing:

chmod 777 "/Volumes/Macintosh HD/"

But I believe that 777 is too much. What's the default umask for ~/.. ?

UPDATE2:

I don't know why it worked since ~/.. means /Users, not /.

Best Answer

I would do two things to restore a Mac in this situation.

  1. boot to recovery mode and run Disk Utility - repair the drive, the volume and then repair permissions.
  2. Boot to recovery mode and run the installer. That should fix or log the exact directory that has improper ACL/permissions and re-create all basic mount points.

The installer log can be read in recovery mode boot if step 2 doesn't fix things and we can perhaps refine exactly what directory or directories are now messed up. There is a chance that you had a separate failure and your chmod was coincidental to the issue as opposed to causative.