On 14.11.23 21:05, Mark Brown wrote:
Since multiple architectures have support for shadow stacks and we need to select support for this feature in several places in the generic code provide a generic config option that the architectures can select.
Suggested-by: David Hildenbrand david@redhat.com Signed-off-by: Mark Brown broonie@kernel.org
arch/x86/Kconfig | 1 + fs/proc/task_mmu.c | 2 +- include/linux/mm.h | 2 +- mm/Kconfig | 6 ++++++ 4 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 3762f41bb092..14b7703a9a2b 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1952,6 +1952,7 @@ config X86_USER_SHADOW_STACK depends on AS_WRUSS depends on X86_64 select ARCH_USES_HIGH_VMA_FLAGS
- select ARCH_HAS_USER_SHADOW_STACK select X86_CET help Shadow stack protection is a hardware feature that detects function
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index ef2eb12906da..f0a904aeee8e 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -699,7 +699,7 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR [ilog2(VM_UFFD_MINOR)] = "ui", #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ -#ifdef CONFIG_X86_USER_SHADOW_STACK +#ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK [ilog2(VM_SHADOW_STACK)] = "ss", #endif }; diff --git a/include/linux/mm.h b/include/linux/mm.h index 418d26608ece..10462f354614 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -341,7 +341,7 @@ extern unsigned int kobjsize(const void *objp); #endif #endif /* CONFIG_ARCH_HAS_PKEYS */ -#ifdef CONFIG_X86_USER_SHADOW_STACK +#ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK /*
- VM_SHADOW_STACK should not be set with VM_SHARED because of lack of
- support core mm.
diff --git a/mm/Kconfig b/mm/Kconfig index 89971a894b60..b8638da636e1 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -1270,6 +1270,12 @@ config LOCK_MM_AND_FIND_VMA bool depends on !STACK_GROWSUP +config ARCH_HAS_USER_SHADOW_STACK
- bool
- help
The architecture has hardware support for userspace shadow callstacks (eg, x86 CET, arm64 GCS, RISC-V Zisslpcfi).
Probably less controversial if we start with one example we have in place: "e.g., x86 CET". That should be sufficient to understand what this is about :)
Acked-by: David Hildenbrand david@redhat.com