From: Mark Brown <broonie@xxxxxxxxxx> 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@xxxxxxxxxx> Acked-by: David Hildenbrand <david@xxxxxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx> Reviewed-by: Deepak Gupta <debug@xxxxxxxxxxxx> Reviewed-by: Carlos Bilbao <carlos.bilbao.osdev@xxxxxxxxx> --- 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 2852fcd82cbd..8ccae77d40f7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1954,6 +1954,7 @@ 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 72f14fd59c2d..23f875e78eae 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -971,7 +971,7 @@ 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 #if defined(CONFIG_64BIT) || defined(CONFIG_PPC32) diff --git a/include/linux/mm.h b/include/linux/mm.h index ecf63d2b0582..57533b9cae95 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -354,7 +354,7 @@ 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 4c9f5ea13271..4b2a1ef9a161 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -1296,6 +1296,12 @@ config NUMA_EMU into virtual nodes when booted with "numa=fake=N", where N is the number of nodes. This is only useful for debugging. +config ARCH_HAS_USER_SHADOW_STACK + bool + help + The architecture has hardware support for userspace shadow call + stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss). + source "mm/damon/Kconfig" endmenu -- 2.45.0