Hi Thiago, On Thu, 04 Jul 2019 15:57:34 -0300 Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx> wrote: > Hello Philipp, > > Philipp Rudo <prudo@xxxxxxxxxxxxx> writes: > > > Hi Thiago, > > > > > > On Thu, 04 Jul 2019 03:42:57 -0300 > > Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx> wrote: > > > >> Jessica Yu <jeyu@xxxxxxxxxx> writes: > >> > >> > +++ Thiago Jung Bauermann [27/06/19 23:19 -0300]: > >> >>IMA will use the module_signature format for append signatures, so export > >> >>the relevant definitions and factor out the code which verifies that the > >> >>appended signature trailer is valid. > >> >> > >> >>Also, create a CONFIG_MODULE_SIG_FORMAT option so that IMA can select it > >> >>and be able to use mod_check_sig() without having to depend on either > >> >>CONFIG_MODULE_SIG or CONFIG_MODULES. > >> >> > >> >>Signed-off-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx> > >> >>Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxx> > >> >>Cc: Jessica Yu <jeyu@xxxxxxxxxx> > >> >>--- > >> >> include/linux/module.h | 3 -- > >> >> include/linux/module_signature.h | 44 +++++++++++++++++++++++++ > >> >> init/Kconfig | 6 +++- > >> >> kernel/Makefile | 1 + > >> >> kernel/module.c | 1 + > >> >> kernel/module_signature.c | 46 ++++++++++++++++++++++++++ > >> >> kernel/module_signing.c | 56 +++++--------------------------- > >> >> scripts/Makefile | 2 +- > >> >> 8 files changed, 106 insertions(+), 53 deletions(-) > >> >> > >> >>diff --git a/include/linux/module.h b/include/linux/module.h > >> >>index 188998d3dca9..aa56f531cf1e 100644 > >> >>--- a/include/linux/module.h > >> >>+++ b/include/linux/module.h > >> >>@@ -25,9 +25,6 @@ > >> >> #include <linux/percpu.h> > >> >> #include <asm/module.h> > >> >> > >> >>-/* In stripped ARM and x86-64 modules, ~ is surprisingly rare. */ > >> >>-#define MODULE_SIG_STRING "~Module signature appended~\n" > >> >>- > >> > > >> > Hi Thiago, apologies for the delay. > >> > >> Hello Jessica, thanks for reviewing the patch! > >> > >> > It looks like arch/s390/kernel/machine_kexec_file.c also relies on > >> > MODULE_SIG_STRING being defined, so module_signature.h will need to be > >> > included there too, otherwise we'll run into a compilation error. > >> > >> Indeed. Thanks for spotting that. The patch below fixes it. It's > >> identical to the previous version except for the changes in > >> arch/s390/kernel/machine_kexec_file.c and their description in the > >> commit message. I'm also copying some s390 people in this email. > > > > to me the s390 part looks good but for one minor nit. > > Thanks for the prompt review! > > > In arch/s390/Kconfig KEXEC_VERIFY_SIG currently depends on > > SYSTEM_DATA_VERIFICATION. I'd prefer when you update this to the new > > MODULE_SIG_FORMAT. It shouldn't make any difference right now, as we don't > > use mod_check_sig in our code path. But it could cause problems in the future, > > when more code might be shared. > > Makes sense. Here is the updated patch with the Kconfig change. > The patch looks good now. Thanks a lot PHilipp
