git init shared=group with a subdir

I believe there may be a bug when initializing a new repository relating to the directory permissions when the --shared=group option is used and the repository is within a sub-directory.

The following will create the "test.git" directory with 2775 permissions (which is as expected):

   $ ls -ld test.git
   ls: cannot access test.git: No such file or directory
   $ git init --bare --shared=group test.git
   Initialized empty shared Git repository in /tmp/test.git/
   $ ls -ld test.git
   drwxrwsr-x 7 pete users 4096 2012-11-14 11:15 test.git

This following will also create the "test.git" directory with 2775 permissions, BUT the "subdir" directory ends up with 755 permissions:

   $ ls -ld subdir
   ls: cannot access subdir: No such file or directory
   $ git init --bare --shared=group subdir/test.git
   Initialized empty shared Git repository in /tmp/subdir/test.git/
   $ ls -ld subdir subdir/test.git
   drwxr-xr-x 3 pete users 4096 2012-11-14 11:16 subdir
   drwxrwsr-x 7 pete users 4096 2012-11-14 11:16 subdir/test.git

Assuming the "subdir" directory doesn't already exist and is created by the "git init" command AND the --shared=group option is used, then shouldn't the "subdir" directory also have 2775 permissions?

petesea@bigfoot.com writes:

People who access this "test.git" does not need to be able to write into subdir/foobar, so the lack of w bit for the group is perfectly fine, no? Depending on to whom you would want to expose things other than "test.git" in "subdir", the desirable set of the permission bits on "subdir" itself would be different, but the "git init" command line does not give us enough information to infer what exact mode is needed.

At least we should give r-x to the parent directories for the classes of users to whom we give rwx to the repository itself. In your example, since we give rwx to user=pete and group=users on "test.git", "subdir" should have r-x (or better) for user=pete and group=users, so that result happens to be correct.

But I do not think we did the right thing by design but it turned out to be correct by accident. If your umask were 077 or something tight, I suspect that we end up creating "subdir" with "rwx------", and group members wouldn't be able to access "test.git". We may want to loosen it down to "rwxr-x---" in such a case, but doing so unconditionally risks exposing things inside "subdir" other than "test.git" to your group members, and worse yet, we would be doing so without telling the user. If your umask is set to a tight value, it is likely that you did so on purpose, and it is debatable if it is a good thing to do. It is safer to create these leading directories like "subdir" honoring the umask, give the user a chance to make sure that other things in "subdir" can be exposed to people who have access to "test.git", and let the user handle the permission (perhaps running "chmod g+rx subdir" as necessary). And that is the behaviour you are observing, I think.