[v5,0/3] KASAN for powerpc/32

Message

Christophe Leroy Feb. 12, 2019, 1:36 p.m. UTC

This serie adds KASAN support to powerpc/32

Tested on nohash/32 (8xx) and book3s/32 (mpc832x ie 603)

Changes in v5:
- Added KASAN_SHADOW_OFFSET in Makefile, otherwise we fallback to KASAN_MINIMAL
and some stuff like stack instrumentation is not performed
- Moved calls to kasan_early_init() in head.S because stack instrumentation
in machine_init was performed before the call to kasan_early_init()
- Mapping kasan_early_shadow_page RW in kasan_early_init() and
remaping RO later in kasan_init()
- Allocating a big memblock() for shadow area, falling back to PAGE_SIZE blocks in case of failure.

Changes in v4:
- Comments from Andrey (DISABLE_BRANCH_PROFILING, Activation of reports)
- Proper initialisation of shadow area in kasan_init()
- Panic in case Hash table is required.
- Added comments in patch one to explain why *t = *s becomes memcpy(t, s, ...)
- Call of kasan_init_tags()

Changes in v3:
- Removed the printk() in kasan_early_init() to avoid build failure (see https://github.com/linuxppc/issues/issues/218)
- Added necessary changes in asm/book3s/32/pgtable.h to get it work on powerpc 603 family
- Added a few KASAN_SANITIZE_xxx.o := n to successfully boot on powerpc 603 family

Changes in v2:
- Rebased.
- Using __set_pte_at() to build the early table.
- Worked around and got rid of the patch adding asm/page.h in asm/pgtable-types.h
    ==> might be fixed independently but not needed for this serie.

For book3s/32 (not 603), it cannot work as is because due to HASHPTE flag, we
can't use the same pagetable for several PGD entries, and because Hash table
management is not not active early enough at the time being.

Christophe Leroy (3):
  powerpc/mm: prepare kernel for KAsan on PPC32
  powerpc/32: Move early_init() in a separate file
  powerpc/32: Add KASAN support

 arch/powerpc/Kconfig                         |   1 +
 arch/powerpc/Makefile                        |   7 ++
 arch/powerpc/include/asm/book3s/32/pgtable.h |   2 +
 arch/powerpc/include/asm/kasan.h             |  24 ++++++
 arch/powerpc/include/asm/nohash/32/pgtable.h |   2 +
 arch/powerpc/include/asm/ppc_asm.h           |   4 +
 arch/powerpc/include/asm/setup.h             |   5 ++
 arch/powerpc/include/asm/string.h            |  14 ++++
 arch/powerpc/kernel/Makefile                 |  11 ++-
 arch/powerpc/kernel/asm-offsets.c            |   4 +
 arch/powerpc/kernel/cputable.c               |  13 ++-
 arch/powerpc/kernel/early_32.c               |  35 ++++++++
 arch/powerpc/kernel/head_32.S                |   3 +
 arch/powerpc/kernel/head_40x.S               |   3 +
 arch/powerpc/kernel/head_44x.S               |   3 +
 arch/powerpc/kernel/head_8xx.S               |   3 +
 arch/powerpc/kernel/head_fsl_booke.S         |   3 +
 arch/powerpc/kernel/prom_init_check.sh       |  10 ++-
 arch/powerpc/kernel/setup-common.c           |   2 +
 arch/powerpc/kernel/setup_32.c               |  28 -------
 arch/powerpc/lib/Makefile                    |   8 ++
 arch/powerpc/lib/copy_32.S                   |   9 ++-
 arch/powerpc/mm/Makefile                     |   3 +
 arch/powerpc/mm/dump_linuxpagetables.c       |   8 ++
 arch/powerpc/mm/kasan_init.c                 | 114 +++++++++++++++++++++++++++
 arch/powerpc/mm/mem.c                        |   4 +
 26 files changed, 285 insertions(+), 38 deletions(-)
 create mode 100644 arch/powerpc/include/asm/kasan.h
 create mode 100644 arch/powerpc/kernel/early_32.c
 create mode 100644 arch/powerpc/mm/kasan_init.c