Re: [RFC PATCH ghak9 0/3] audit: Record the path of FDs passed to *at(2) syscalls

Steve Grubb
2018-07-25T12:48:22Z

On Wednesday, July 25, 2018 3:44:07 AM EDT Ondrej Mosnacek wrote:
> On Wed, Jul 25, 2018 at 3:11 AM Steve Grubb <sgrubb@redhat.com> wrote:
> > On Tuesday, July 24, 2018 6:15:54 PM EDT Paul Moore wrote:
> > > On Tue, Jul 24, 2018 at 10:12 AM Ondrej Mosnacek <omosnace@redhat.com>
> > >
> > > > Beyond that, there is really no information in the records that would
> > > > allow reconstructing which PARENT path belongs to which CREATE/DELETE
> > > > path... (Intuitively you can guess that src will come before dst, but
> > > > that is not very reliable.) I think a "parent inode" field in the
> > > > PATH
> > > > records could fix this, but maybe there is a better solution...
> > >
> > > I have my suspicions, but I would be curious to hear from Steve how
> > > the reconstruction is typically handled.
> >
> > For any *at function when the dirfd is not AT_FDCWD, it goes badly. If
> > its a old style syscall without the dirfd, then if the first character
> > is '/' use that. Otherwise concatonate cwd and path and pass it to
> > realpath to sort out.
>
> In that case it seems the best fix for openat() et al. would be to
> somehow always force outputting the full path when dirfd != AT_FDCWD.
> Hopefully that won't require too much hacking around...

What is asked for is the full path that dirfd was opened with. I can take
care of everything else.

-Steve