Re: [PATCH] Check multiple NT_GNU_PROPERTY_TYPE_0 notes [BZ #23509]

[Florian Weimer <fweimer at redhat dot com>]

On 08/15/2018 05:23 PM, H.J. Lu wrote:
> On Wed, Aug 15, 2018 at 8:17 AM, Florian Weimer <fweimer@redhat.com> wrote:
> > On 08/14/2018 08:12 PM, H.J. Lu wrote:
> > > _dl_process_cet_property_note is called on on each PT_NOTE segment.
> > > We must keep searching until we found a PT_NOTE segment with a
> > > NT_GNU_PROPERTY_TYPE_0 note:
> > >
> > >     /* Skip if we have seen a NT_GNU_PROPERTY_TYPE_0 note before.  */
> > >     if (l->l_cet != lc_unknown)
> > >       return;
> > > ...
> >
> >
> > What if there are different segments, each one with its own
> > NT_GNU_PROPERTY_TYPE_0?  Wouldn't that point to lack of linker support, too?
> > So that CET needs to be disabled?
>
> Older linkers puts all NT_GNU_PROPERTY_TYPE_0 notes in one
> .note.gnu.property section.  One can certainly create some random notes
> which look like NT_GNU_PROPERTY_TYPE_0.  I don't think we need to
> check these notes.

I think older BFD ld creates multiple segments.

Thanks,
Florian