Re: Use current directory for POSIX mkdir test in install-sh

[Alex Unleashed]

On 10/10/06, Paul Eggert <address@hidden> wrote:
> > The difference with other mkdir versions is that GNU mkdir does not try
> to
> > chmod() the directory if it didn't just create it. The mkdir I'm
> currently
> > testing is FreeBSD's. It always chmod()'s the directory when a mode is
> > specified, no matter it didn't create it.
>
> Ouch!
>
> That behavior is incorrect; it doesn't conform to POSIX.  You might
> file a bug report, citing
> < http://www.opengroup.org/onlinepubs/009695399/utilities/mkdir.html >.
Will do. Thanks for the link.

> This chmod(), even when failing,
> > is considered an attempt to write to an external path,
>
> That's weird.  mkdir("/", ...) is not considered to be an attempt to
> write to an external file name, but chmod ("/", ...) is?  This doesn't
> sound consistent to me; both system calls _attempt_ to write to an
> external file name.  And neither _succeeds_ (which is what should
> matter here).  So it sounds like your sandbox tests should be
> adjusted, one way or another, since they're not consistent.


Yup, that's a known issue in the sandboxing code, and it would certainly
trigger the mkdir call once fixed. But the fact of the attempt is what
really matters, as we cannot predict if the call will fail, and if it
succeeds it would actually change the file system, which is an unacceptable
risk.

Thanks,

Alex