The following commit has been merged into the x86/shstk branch of tip:
Commit-ID: 4c8e07c3b6db4a514b03f2f2455e81e512d2f785
Gitweb: https://git.kernel.org/tip/4c8e07c3b6db4a514b03f2f2455e81e512d2f785
Author: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
AuthorDate: Sat, 18 Mar 2023 17:15:17 -07:00
Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CommitterDate: Mon, 20 Mar 2023 09:01:10 -07:00
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 <yu-cheng.yu@xxxxxxxxx>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
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>
Link: https://lore.kernel.org/all/20230319001535.23210-23-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 7920a8b..2e9f313 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -491,14 +491,14 @@ 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);
}
/*
|