kasan: add functions for unpoisoning stack variables

As a code-size optimization, LLVM builds since r279383 may bulk-manipulate
the shadow region when (un)poisoning large memory blocks.  This requires
new callbacks that simply do an uninstrumented memset().

This fixes linking the Clang-built kernel when using KASAN.

[[email protected]: add declarations for internal functions]
  Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: __asan_set_shadow_00 can be static]
  Link: http://lkml.kernel.org/r/20171223125943.GA74341@lkp-ib03
[[email protected]: fix memset() parameters, and tweak commit message to describe new callbacks]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Alexander Potapenko <[email protected]>
Signed-off-by: Greg Hackmann <[email protected]>
Signed-off-by: Paul Lawrence <[email protected]>
Signed-off-by: Fengguang Wu <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Acked-by: Andrey Ryabinin <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Masahiro Yamada <[email protected]>
Cc: Matthias Kaehlcke <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions