Re: odb_mkstemp's 0444 permission broke write/delete access on AFP

From: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Date: Feb 16, 2015, 18:23 UTC
Message-ID: <vpqtwyl90mx.fsf@anie.imag.fr>
In-Reply-To: <A403BFCC-D66F-49BD-B54C-BB86B467F1A1@gmail.com>

Fairuzan Roslan <fairuzan.roslan@gmail.com> writes:

Show 5 quoted lines

> Hi,
>
> Somehow the “int mode = 0444;” in odb_mkstemp (environment.c) are
> causing a lot of issues (unable to unlink/write/rename) to those
> people who use AFP shares.

Is it a problem when using Git (like "git gc" failing to remove old packs), or when trying to remove files outside Git?

> The issue was first introduced in
> https://github.com/git/git/blob/f80c7ae8fe9c0f3ce93c96a2dccaba34e456e33a/wrapper.c
> line 284.

I don't think so. The code before this commit did essentially a chmod 444 on the file, so object files were already read-only before.

The pack files have been read-only since d83c9af5c6a437ddaa9dd27 (Junio, Apr 22 2007).

> To fix these issues the permission need to be adjusted to “int mode =
> 0644;” in odb_mkstemp (environment.c)

The issue is that having object and pack files read-only on the filesystem is a safety feature to prevent accidental modifications (even though it's actually not that effective, since brute-force "sed -i" or "perl -i" still accept to modify read-only files).

So, I'd be a bit reluctant to remove this safety feature for all users if it's only for the benefit of a minority of users. Not that I think the problem shouldn't be fixed, but I'd rather investigate alternate solutions before using this mode = 0644.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/