On Tue, 13 Oct 2020 at 18:46, Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote: > > [Cc'ing linuxppc-dev@xxxxxxxxxxxxxxxx] > > On Tue, 2020-10-13 at 10:18 +0200, Ard Biesheuvel wrote: > > Chester reports that it is necessary to introduce a new way to pass > > the EFI secure boot status between the EFI stub and the core kernel > > on ARM systems. The usual way of obtaining this information is by > > checking the SecureBoot and SetupMode EFI variables, but this can > > only be done after the EFI variable workqueue is created, which > > occurs in a subsys_initcall(), whereas arch_ima_get_secureboot() > > is called much earlier by the IMA framework. > > > > However, the IMA framework itself is started as a late_initcall, > > and the only reason the call to arch_ima_get_secureboot() occurs > > so early is because it happens in the context of a __setup() > > callback that parses the ima_appraise= command line parameter. > > > > So let's refactor this code a little bit, by using a core_param() > > callback to capture the command line argument, and deferring any > > reasoning based on its contents to the IMA init routine. > > > > Cc: Chester Lin <clin@xxxxxxxx> > > Cc: Mimi Zohar <zohar@xxxxxxxxxxxxx> > > Cc: Dmitry Kasatkin <dmitry.kasatkin@xxxxxxxxx> > > Cc: James Morris <jmorris@xxxxxxxxx> > > Cc: "Serge E. Hallyn" <serge@xxxxxxxxxx> > > Link: https://lore.kernel.org/linux-arm-kernel/20200904072905.25332-2-clin@xxxxxxxx/ > > Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > > --- > > v2: rebase onto series 'integrity: improve user feedback for invalid bootparams' > > Thanks, Ard. Based on my initial, limited testing on Power, it looks > good, but I'm hesistant to include it in the integrity 5.10 pull > request without it having been in linux-next and some additional > testing. It's now queued in the next-integrity-testing branch awaiting > some tags. > Thanks. No rush as far as I am concerned, although I suppose Chester may want to rebase his arm64 IMA enablement series on this. Suggestion: can we take the get_sb_mode() code from ima_arch.c in arch/x86, and generalize it for all EFI architectures? That way, we can enable 32-bit ARM and RISC-V seamlessly once someone gets around to enabling IMA on those platforms. In fact, get_sb_mode() itself should probably be factored out into a generic helper for use outside of IMA as well (Xen/x86 has code that does roughly the same already)
