From 00547ef73ff282eea59cd33b8952f1dcbb4bd4b8 Mon Sep 17 00:00:00 2001 From: Rick Edgecombe Date: Mon, 12 Jun 2023 17:10:45 -0700 Subject: mm/mmap: Add shadow stack pages to memory accounting The x86 Control-flow Enforcement Technology (CET) feature includes a new type of memory called shadow stack. This shadow stack memory has some unusual properties, which requires some core mm changes to function properly. Co-developed-by: Yu-cheng Yu Signed-off-by: Yu-cheng Yu Signed-off-by: Rick Edgecombe Signed-off-by: Dave Hansen Reviewed-by: Borislav Petkov (AMD) Reviewed-by: Kees Cook Acked-by: Mike Rapoport (IBM) Acked-by: David Hildenbrand Tested-by: Pengfei Xu Tested-by: John Allen Tested-by: Kees Cook Link: https://lore.kernel.org/all/20230613001108.3040476-20-rick.p.edgecombe%40intel.com --- mm/internal.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index a7d9e980429a..018f5c342f90 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -538,14 +538,14 @@ static inline bool is_exec_mapping(vm_flags_t flags) } /* - * Stack area - automatically grows in one direction + * Stack area (including shadow stacks) * * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous: * do_mmap() forbids all other combinations. */ static inline bool is_stack_mapping(vm_flags_t flags) { - return (flags & VM_STACK) == VM_STACK; + return ((flags & VM_STACK) == VM_STACK) || (flags & VM_SHADOW_STACK); } /* -- cgit v1.2.3