[PATCH v1 0/8] powerpc/32s: Allocate modules outside of vmalloc space for STRICT_KERNEL_RWX

Christophe Leroy christophe.leroy at csgroup.eu
Sat Jun 20 01:06:50 AEST 2020


On book3s32 (hash), exec protection is set per 256Mb segments with NX bit.
Instead of clearing NX bit on vmalloc space when CONFIG_MODULES is selected,
allocate modules in a dedicated segment (0xb0000000-0xbfffffff by default).
This allows to keep exec protection on vmalloc space while allowing exec
on modules.

Christophe Leroy (8):
  powerpc/ptdump: Refactor update of st->last_pa
  powerpc/ptdump: Refactor update of pg_state
  powerpc: Set user/kernel boundary at TASK_SIZE instead of PAGE_OFFSET
  powerpc/lib: Prepare code-patching for modules allocated outside
    vmalloc space
  powerpc: Use MODULES_VADDR if defined
  powerpc/32s: Only leave NX unset on segments used for modules
  powerpc/32s: Kernel space starts at TASK_SIZE
  powerpc/32s: Use dedicated segment for modules with STRICT_KERNEL_RWX

 arch/powerpc/Kconfig                         |  1 +
 arch/powerpc/include/asm/book3s/32/pgtable.h | 15 ++----
 arch/powerpc/include/asm/page.h              |  2 +-
 arch/powerpc/kernel/head_32.S                | 12 ++---
 arch/powerpc/kernel/module.c                 | 11 ++++
 arch/powerpc/lib/code-patching.c             |  2 +-
 arch/powerpc/mm/book3s32/hash_low.S          |  2 +-
 arch/powerpc/mm/book3s32/mmu.c               | 17 +++++--
 arch/powerpc/mm/kasan/kasan_init_32.c        |  6 +++
 arch/powerpc/mm/ptdump/ptdump.c              | 53 ++++++++++++--------
 10 files changed, 78 insertions(+), 43 deletions(-)

-- 
2.25.0



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