Hello Philipp, Philipp Rudo <prudo@xxxxxxxxxxxxx> writes: > 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! Can I add your Reviewed-by? -- Thiago Jung Bauermann IBM Linux Technology Center
