Subject: Re: [PATCH] Fix backwards-incompatible handling of core.sharedRepository

From: Junio C Hamano <[email-masked]>
Date: Thu, 10 Jul 2008 22:34:57 -0700

Junio C Hamano <[email-masked]> writes:

> Petr Baudis <[email-masked]> writes:
>
>> The 06cbe8550324e0fd2290839bf3b9a92aa53b70ab core.sharedRepository
>> handling extension broke backwards compatibility; before, shared=1 meant
>> that Git merely ensured the repository is group-writable, not that it's
>> _only_ group-writable, which is the current behaviour.
>
> Donn't our existing tests catch this, and if the answer is no because we
> don't have any, could you add some?
> ...
>> diff --git a/path.c b/path.c
>> index 5983255..75c5915 100644
>> --- a/path.c
>> +++ b/path.c
>> @@ -269,7 +269,7 @@ int adjust_shared_perm(const char *path)
>>  	mode = st.st_mode;
>>  
>>  	if (shared_repository) {
>> -		int tweak = shared_repository;
>> +		int tweak = (mode & 0777) | shared_repository;
>>  		if (!(mode & S_IWUSR))
>>  			tweak &= ~0222;
>>  		mode = (mode & ~0777) | tweak;
>
> I think this change is good.  shared_repository has always been about
> widening the access and not about limiting.

Having said that, you really should protect this behaviour from regression
with a test case.  I do not see practical difference for sane umask
values.

What umask are you using, and which file in the repository gets affected?
In the old code I see we do have checks for S_IXUSR and tweaks on S_IXGRP
and S_IXOTH, but this should make a difference only if your umask blocks
executable bit and the file in question is executable.  Was it an
executable hook copied from template?