Merge tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull usercopy protection from Kees Cook:
 "Tbhis implements HARDENED_USERCOPY verification of copy_to_user and
  copy_from_user bounds checking for most architectures on SLAB and
  SLUB"

* tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  mm: SLUB hardened usercopy support
  mm: SLAB hardened usercopy support
  s390/uaccess: Enable hardened usercopy
  sparc/uaccess: Enable hardened usercopy
  powerpc/uaccess: Enable hardened usercopy
  ia64/uaccess: Enable hardened usercopy
  arm64/uaccess: Enable hardened usercopy
  ARM: uaccess: Enable hardened usercopy
  x86/uaccess: Enable hardened usercopy
  mm: Hardened usercopy
  mm: Implement stack frame object validation
  mm: Add is_migrate_cma_page

1 files changed, 9 insertions, 0 deletions

diff --git a/arch/Kconfig b/arch/Kconfig
index bd8056b5b246..e9c9334507dd 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -461,6 +461,15 @@ config CC_STACKPROTECTOR_STRONG
 
 endchoice
 
+config HAVE_ARCH_WITHIN_STACK_FRAMES
+        bool
+        help
+          An architecture should select this if it can walk the kernel stack
+          frames to determine if an object is part of either the arguments
+          or local variables (i.e. that it excludes saved return addresses,
+          and similar) by implementing an inline arch_within_stack_frames(),
+          which is used by CONFIG_HARDENED_USERCOPY.
+
 config HAVE_CONTEXT_TRACKING
         bool
         help