Re: [PATCH v26 0/9] Control-flow Enforcement: Indirect Branch Tracking

[Andy Lutomirski]

On Wed, Apr 28, 2021 at 7:48 AM David Laight <David.Laight@xxxxxxxxxx> wrote:
>
> From: Yu-cheng Yu
> > Sent: 27 April 2021 21:47
> >
> > Control-flow Enforcement (CET) is a new Intel processor feature that blocks
> > return/jump-oriented programming attacks.  Details are in "Intel 64 and
> > IA-32 Architectures Software Developer's Manual" [1].
> ...
>
> Does this feature require that 'binary blobs' for out of tree drivers
> be compiled by a version of gcc that adds the ENDBRA instructions?
>
> If enabled for userspace, what happens if an old .so is dynamically
> loaded?
> Or do all userspace programs and libraries have to have been compiled
> with the ENDBRA instructions?

If you believe that the userspace tooling for the legacy IBT table
actually works, then it should just work.  Yu-cheng, etc: how well
tested is it?

--Andy