Re: [PATCH] cygwin: set write permission before unlink
- From
- Rei Thiessen <rei.thiessen@gmail.com>
- Date
- Jun 29, 2011, 18:48 UTC
- Message-ID
- <BANLkTincfBvDBYYLGJe-m5hknvCVdmMUww@mail.gmail.com>
- In-Reply-To
- <09c0b1900a67bd1f701c0b23954a34ab.squirrel@mail.localhost.li>
Another point of concern is that the user might have specifically set the read-only flag only certain files to protect them from changes/deletion, but after the patch, git can delete them with impunity. But then, a file's permission isn't supposed to matter to unlink() anyways. Interestingly, Cygwin's packaged unlink command-line utility will delete read-only files, so Cygwin's attempt to fake permissions through the read-only flag when a filesystem is mounted with "noacl" seems to be inconsistent.
I'll leave this issue up to Cygwin's package maintainer for git.
Regards, Rei
2011/6/29 Christof Krüger <git@christof-krueger.de>:
Show 19 quoted lines
>> +#undef unlink
>> +int cygwin_unlink(const char *pathname)
>> +{
>> + /* "read-only" files can't be unlinked */
>> + chmod(pathname, 0666);
>> + return unlink(pathname);
>> +}
>
> I've no idea on how cygwin maps file permissions to the underlying
> filesystem, but the above raised my attention. Doesn't chmodding the file
> to 0666 open a small windows where "group" and "other" users have read
> access to the file? This might be unwanted by the user and could be
> exploited by some attacker listening for changes on that file.
> Or am I too paranoid?
>
> Regards,
> Chris
>
>