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 <yu-cheng.yu@xxxxxxxxx>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
Reviewed-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Tested-by: Pengfei Xu <pengfei.xu@xxxxxxxxx>
Tested-by: John Allen <john.allen@xxxxxxx>
Tested-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
mm/internal.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/internal.h b/mm/internal.h
index 68410c6d97ac..dd2ded32d3d5 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -535,14 +535,14 @@ 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);
}
/*
--
2.34.1
