Major Permissions Screw-UP

[Kalypso]

I am new to OSX and macs in general, and was working on a new macbook pro. I noticed when I turned on file sharing, the root macosx drive was shared by default, and I wanted to disable this. I clicked on "get info" for the drive, and then under "sharing and permissions" I started to change entries (not realizing obviously that it applied to the LOCAL user permissions). Now, I have absolutely zero access to my main drive! I can see the only remaining group with read/write access is the "system" account.


Please advise on my next step. I don't want to restart or try a repair install for fear of not being able to log back in at all.

This is extremely frustrating as you might guess.
Thank you!

 

[Kalypso]

Alright so it took me a few hours but I figured it out.
For the record:
-Do not bother trying to repair disk permissions w/ the start up disk. it will fail.
-also don't do a repair/archive install. it will probably fail and screw up all your settings/apps...
Instead....

-reboot into "single user mode"

by holding down (command + s) on reboot​

.
-fix the disk and mount as read/write

/sbin/fsck -fy /​

/sbin/mount -uw /​

-reset write permissions for the disk owner

chmod o+w /​

-reset execute permissions for the disk owner

chmod o+x /​

-reset all permissions for the disk (redundant but thorough)

chmod 755 /​

chmod -R ugo+X /​

-continue the boot

exit​

-Once booted and logged in, go and reset permissions by right clicking on disk and selecting "get info"