Re: [PATCH v5 2/6] powerpc/kexec_file: Add KEXEC_SIG support.

From: Mimi Zohar
Date: Sun Feb 13 2022 - 22:01:03 EST


Hi Michal,

On Tue, 2022-01-11 at 12:37 +0100, Michal Suchanek wrote:
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index dea74d7717c0..1cde9b6c5987 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -560,6 +560,22 @@ config KEXEC_FILE
> config ARCH_HAS_KEXEC_PURGATORY
> def_bool KEXEC_FILE
>
> +config KEXEC_SIG
> + bool "Verify kernel signature during kexec_file_load() syscall"
> + depends on KEXEC_FILE && MODULE_SIG_FORMAT
> + help
> + This option makes kernel signature verification mandatory for
> + the kexec_file_load() syscall.

When KEXEC_SIG is enabled on other architectures, IMA does not define a
kexec 'appraise' policy rule. Refer to the policy rules in
security/ima/ima_efi.c. Similarly the kexec 'appraise' policy rule in
arch/powerpc/kernel/ima_policy.c should not be defined.

--
thanks,

Mimi