On Mon, Jun 15, 2020 at 10:59 AM Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote: > > On Mon, 2020-06-15 at 09:33 -0400, Stephen Smalley wrote: > > On Fri, Jun 12, 2020 at 10:42 PM Lakshmi Ramasubramanian > > <nramas@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > > The data maintained by the security modules could be tampered with by > > > malware. The LSM needs to periodically query the state of > > > the security modules and measure the data when the state is changed. > > > > > > Define a workqueue for handling this periodic query and measurement. > > > > Won't this make it difficult/impossible to predict the IMA PCR value? > > Unless I missed it, you are going to end up measuring every N minutes > > even if there was no change and therefore constantly be extending the > > PCR. That will break attestation or sealing against the IMA PCR. > > Even if it attempts to add the same measurement to the list multiple > times, unless something changed, there should only be one measurement > in the list. Is the PCR only extended once?
