Cannot cd into directory even though group has permissions

Question

I'm aware that there are other similar questions, but nothing in there solved my issue.

gitlab-runner@my-machine:~$ groups
gitlab-runner my-user

gitlab-runner@my-machine:~$ sudo ls -l /home
total 16
drwxrwsr-x+ 16 my-user my-user 4096 Feb 13 09:22 my-user
# ... other users' homes omitted ...

gitlab-runner@my-machine:~$ sudo ls -l /home/my-user
total 528
drwsrws---+ 4 my-user my-user 4096 Jun  7  2020 my-dir
# ... irrelevant files omitted ...

gitlab-runner@my-machine:~$ sudo ls -l /home/my-user/my-dir
total 48
drwxrwsr-x+ 7 my-user my-user 4096 Aug 12  2021 my-dir
drwxrwsr-x+ 6 my-user my-user 4096 Jun  7  2020 venv

gitlab-runner@my-machine:~$ cd /home/my-user/my-dir
-bash: cd: /home/my-user/my-dir: Permission denied

The user is a member of the group, the group has read and execute permissions on the target folder and the home it's contained in, and yet the user cannot cd into it. I have also tried logout and then sudo - gitlab-runner again, but it still doesn't work. Why?

I'm unsure why the x bit shows s and I can't find an explanation anywhere. Maybe that's relevant but I don't know what it means nor how to change it, since sudo chmod g+x doesn't change it.

Answer 1

It turns out that I had ACLs set for that folder, as @raj correctly pointed out in the comments.

I was under the mistaken impression that ACL permissions would be ORed to the permission bits, whereas instead they entirely override them. My ACL for the directory had rw- permissions, the x bit was missing, and so I had no permissions to cd there with that user.