Mimi Zohar <zohar@xxxxxxxxxxxxx> writes: > On Mon, 2020-03-02 at 15:52 +0100, Ard Biesheuvel wrote: >> On Mon, 2 Mar 2020 at 15:48, Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote: >> > >> > On Wed, 2020-02-26 at 14:10 -0500, Nayna Jain wrote: >> > > Every time a new architecture defines the IMA architecture specific >> > > functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA >> > > include file needs to be updated. To avoid this "noise", this patch >> > > defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing >> > > the different architectures to select it. >> > > >> > > Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> >> > > Signed-off-by: Nayna Jain <nayna@xxxxxxxxxxxxx> >> > > Cc: Ard Biesheuvel <ardb@xxxxxxxxxx> >> > > Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> >> > > Cc: Philipp Rudo <prudo@xxxxxxxxxxxxx> >> > > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> >> > > --- >> > > arch/powerpc/Kconfig | 2 +- >> > > arch/s390/Kconfig | 1 + >> > > arch/x86/Kconfig | 1 + >> > > include/linux/ima.h | 3 +-- >> > > security/integrity/ima/Kconfig | 9 +++++++++ >> > > 5 files changed, 13 insertions(+), 3 deletions(-) >> > > >> > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig >> > > index 497b7d0b2d7e..b8ce1b995633 100644 >> > > --- a/arch/powerpc/Kconfig >> > > +++ b/arch/powerpc/Kconfig >> > > @@ -246,6 +246,7 @@ config PPC >> > > select SYSCTL_EXCEPTION_TRACE >> > > select THREAD_INFO_IN_TASK >> > > select VIRT_TO_BUS if !PPC64 >> > > + select IMA_SECURE_AND_OR_TRUSTED_BOOT if PPC_SECURE_BOOT >> > > # >> > > # Please keep this list sorted alphabetically. >> > > # >> > > @@ -978,7 +979,6 @@ config PPC_SECURE_BOOT >> > > prompt "Enable secure boot support" >> > > bool >> > > depends on PPC_POWERNV >> > > - depends on IMA_ARCH_POLICY >> > > help >> > > Systems with firmware secure boot enabled need to define security >> > > policies to extend secure boot to the OS. This config allows a user >> > > diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig >> > > index 8abe77536d9d..90ff3633ade6 100644 >> > > --- a/arch/s390/Kconfig >> > > +++ b/arch/s390/Kconfig >> > > @@ -195,6 +195,7 @@ config S390 >> > > select ARCH_HAS_FORCE_DMA_UNENCRYPTED >> > > select SWIOTLB >> > > select GENERIC_ALLOCATOR >> > > + select IMA_SECURE_AND_OR_TRUSTED_BOOT >> > > >> > > >> > > config SCHED_OMIT_FRAME_POINTER >> > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig >> > > index beea77046f9b..cafa66313fe2 100644 >> > > --- a/arch/x86/Kconfig >> > > +++ b/arch/x86/Kconfig >> > > @@ -230,6 +230,7 @@ config X86 >> > > select VIRT_TO_BUS >> > > select X86_FEATURE_NAMES if PROC_FS >> > > select PROC_PID_ARCH_STATUS if PROC_FS >> > > + select IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI >> > >> > Not everyone is interested in enabling IMA or requiring IMA runtime >> > policies. With this patch, enabling IMA_ARCH_POLICY is therefore >> > still left up to the person building the kernel. As a result, I'm >> > seeing the following warning, which is kind of cool. >> > >> > WARNING: unmet direct dependencies detected for >> > IMA_SECURE_AND_OR_TRUSTED_BOOT >> > Depends on [n]: INTEGRITY [=y] && IMA [=y] && IMA_ARCH_POLICY [=n] >> > Selected by [y]: >> > - X86 [=y] && EFI [=y] >> > >> > Ard, Michael, Martin, just making sure this type of warning is >> > acceptable before upstreaming this patch. I would appreciate your >> > tags. >> > >> >> Ehm, no, warnings like these are not really acceptable. It means there >> is an inconsistency in the way the Kconfig dependencies are defined. >> >> Does this help: >> >> select IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI && IMA_ARCH_POLICY >> >> ? > > Yes, that's fine for x86. Michael, Martin, do you want something > similar or would you prefer actually selecting IMA_ARCH_POLICY? For powerpc this should be all we need: diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 497b7d0b2d7e..a5cfde432983 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -976,12 +976,13 @@ config PPC_MEM_KEYS config PPC_SECURE_BOOT prompt "Enable secure boot support" bool depends on PPC_POWERNV depends on IMA_ARCH_POLICY + select IMA_SECURE_AND_OR_TRUSTED_BOOT help Systems with firmware secure boot enabled need to define security policies to extend secure boot to the OS. This config allows a user to enable OS secure boot on systems that have firmware support for it. If in doubt say N. cheers