Re: [PATCH v7 22/27] binfmt_elf: Extract .note.gnu.property from an ELF file

From: Yu-cheng Yu
Date: Tue Jun 18 2019 - 12:13:49 EST


On Tue, 2019-06-18 at 18:05 +0200, Florian Weimer wrote:
> * Yu-cheng Yu:
>
> > > I assumed that it would also parse the main executable and make
> > > adjustments based on that.
> >
> > Yes, Linux also looks at the main executable's header, but not its
> > NT_GNU_PROPERTY_TYPE_0 if there is a loader.
> >
> > >
> > > ld.so can certainly provide whatever the kernel needs. We need to tweak
> > > the existing loader anyway.
> > >
> > > No valid statically-linked binaries exist today, so this is not a
> > > consideration at this point.
> >
> > So from kernel, we look at only PT_GNU_PROPERTY?
>
> If you don't parse notes/segments in the executable for CET, then yes.
> We can put PT_GNU_PROPERTY into the loader.

Thanks!