On Fri, 3 Feb 2017 14:29:04 -0500
Michael Orlitzky <mjo@gentoo.org> wrote:

> > However, it is no rocket science to write a race-free chown command
> > in C: Just open the file and use stat() and fchown() to be sure to
> > change only files from the "correct" user.
> > 
> > Since this works on the filehandle and not on the filename, I think
> > that there is no possibility for an exploit when this is used in the
> > above find loop.  
> 
> Not a bad idea... we chould ship that safe-chown utility, and then
> tell users how to use it to fix their UIDs. The draft that I wrote up
> was for the "fixed UID with random fallback" model, but said utility
> could still be useful for people who want to change their running
> systems to use the same UIDs that would have been chosen by default.

Are you sure that said utility isn’t simply “chown --from”?
-- 
Christopher Head