On Tue, 2020-03-03 at 21:33 -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: Philipp Rudo <prudo@xxxxxxxxxxxxx> > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > --- > v2: > * Fixed the issue identified by Mimi. Thanks Mimi, Ard, Heiko and > Michael for > discussing the fix. > > arch/powerpc/Kconfig | 1 + > arch/s390/Kconfig | 1 + > arch/x86/Kconfig | 1 + > include/linux/ima.h | 3 +-- > security/integrity/ima/Kconfig | 9 +++++++++ > 5 files changed, 13 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 497b7d0b2d7e..a5cfde432983 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -979,6 +979,7 @@ config PPC_SECURE_BOOT > 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 > diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig > index 8abe77536d9d..4a502fbcb800 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 if IMA_ARCH_POLICY > > > config SCHED_OMIT_FRAME_POINTER > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index beea77046f9b..7f5bfaf0cbd2 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 && > IMA_ARCH_POLICY > > config INSTRUCTION_DECODER > def_bool y > diff --git a/include/linux/ima.h b/include/linux/ima.h > index 1659217e9b60..aefe758f4466 100644 > --- a/include/linux/ima.h > +++ b/include/linux/ima.h > @@ -30,8 +30,7 @@ extern void ima_kexec_cmdline(const void *buf, int > size); > extern void ima_add_kexec_buffer(struct kimage *image); > #endif > > -#if (defined(CONFIG_X86) && defined(CONFIG_EFI)) || > defined(CONFIG_S390) \ > - || defined(CONFIG_PPC_SECURE_BOOT) > +#ifdef CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT > extern bool arch_ima_get_secureboot(void); > extern const char * const *arch_get_ima_policy(void); > #else > diff --git a/security/integrity/ima/Kconfig > b/security/integrity/ima/Kconfig > index 3f3ee4e2eb0d..d17972aa413a 100644 > --- a/security/integrity/ima/Kconfig > +++ b/security/integrity/ima/Kconfig > @@ -327,3 +327,12 @@ config IMA_QUEUE_EARLY_BOOT_KEYS > depends on IMA_MEASURE_ASYMMETRIC_KEYS > depends on SYSTEM_TRUSTED_KEYRING > default y > + > +config IMA_SECURE_AND_OR_TRUSTED_BOOT > + bool > + depends on IMA > + depends on IMA_ARCH_POLICY > + default n You can't do this: a symbol designed to be selected can't depend on other symbols because Kconfig doesn't see the dependencies during select. We even have a doc for this now: Documentation/kbuild/Kconfig.select-break The only way to get this to work would be to have the long name symbol select both IMA and IMA_ARCH_POLICY, which doesn't seem to be what you want either. Looking at what you're trying to do, I think making the symbol independent of IMA and IMA_ARCH_POLICY is the correct thing, then enforce the dependencies inside the outer #ifdef, but I haven't looked deeply at the code. James
