git: can't push (unpacker error) related to permission issues

I have this problem when i try to push in git:

error: insufficient permission for adding an object to repository database ./objects

fatal: failed to write object
error: unpack failed: unpack-objects abnormal exit
To ssh://<repo url>/<repo dir>
 ! [remote rejected] master -> master (n/a (unpacker error))
error: failed to push some refs to 'ssh://<repo url>/<repo dir>'

I've had this before sporadically and we've always had to solve it by each user sshing to the repo and setting group permissions on all the files therein with

chmod -R g+w *

This was never a satisfactory solution and now it's bitten us in the arse as one of the guys is away and no-one knows his repo user's password. So, i'm trying to solve it properly.

The error seems to occur when someone tries to push up a change that will alter a repo dir that is owned by another user (hence setting the group write option above). I've done a bit of googling around this and have found a couple of solutions being discussed (neither of which worked for me)

1) make sure that the group that the repo dirs are shared with is each users' primary group (i believe that is the case already: each user has only one group so that must be their primary group, right?)

2) git repo core.sharedRepository setting, as detailed here: Git: Can't push from one computer I changed this but it didn't make any difference. Do i need to reload the config or something to actually effect the change?

Here's what my repo config looks like atm:

[core]
        repositoryformatversion = 0
        filemode = true
        bare = true
        sharedRepository = all
[receive]
        denyNonFastForwards = True

Grateful for any advice or suggestions! max

Solution 1:

I had this error for two weeks, and the majority of the solutions stated 'chmod -R' as the the answer, unfortunately for me my git repos (local / remote / shared - with team) were all on Windows OS, and even though chmod -Rv showed all the files changed to 'rwxrwxrwx', a subsequent 'ls -l' still showed all files as 'rwxr-xr-x' and the error repeated itself. I eventually saw this solution by Ariejan de Vroom. It worked and we were all able to pull and push again.

On both local (the local that is having trouble pushing) and remote repos, run the following commands:

$ git fsck
$ git prune
$ git repack
$ git fsck

On a side note, I tried using Windows' native file permissions / ACL and even resorted to elevating the problem user to Administrator, but none of that seemed to help. Not sure if the environment is important, but it may help someone with a similar setup - problem team member and remote (Windows Server 2008 R2 Standard), my local (Windows 7 VM).

Solution 2:

A simpler way to do this is to add a post-receive script which runs the chmod command after every push to the 'hub' repo on the server. Add the following line to hooks/post-receive inside your git folder on the server:

chmod -Rf u+w /path/to/git/repo/objects

Solution 3:

It is a permission error. The way that was most appropriate and secure for me was adding users to a supplementary group that the repo. is owned by (or vice versa):

groupadd git
chgrp -R git .git
chgrp -R git ./
usermod -G -a git $(whoami)

Solution 4:

In case anyone else is stuck with this: it just means the write permissions are wrong in the repo that you’re pushing to. Go and chmod -R it so that the user you’re accessing the git server with has write access.