[lkml]   [2021]   [Dec]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Subject[PATCH mm v3 00/38] kasan, vmalloc, arm64: add vmalloc tagging support for SW/HW_TAGS
From: Andrey Konovalov <>


This patchset adds vmalloc tagging support for SW_TAGS and HW_TAGS
KASAN modes.

The tree with patches is available here:

About half of patches are cleanups I went for along the way. None of
them seem to be important enough to go through stable, so I decided
not to split them out into separate patches/series.

The patchset is partially based on an early version of the HW_TAGS
patchset by Vincenzo that had vmalloc support. Thus, I added a
Co-developed-by tag into a few patches.

SW_TAGS vmalloc tagging support is straightforward. It reuses all of
the generic KASAN machinery, but uses shadow memory to store tags
instead of magic values. Naturally, vmalloc tagging requires adding
a few kasan_reset_tag() annotations to the vmalloc code.

HW_TAGS vmalloc tagging support stands out. HW_TAGS KASAN is based on
Arm MTE, which can only assigns tags to physical memory. As a result,
HW_TAGS KASAN only tags vmalloc() allocations, which are backed by
page_alloc memory. It ignores vmap() and others.

Changes in v2->v3:
- Rebase onto mm.
- New patch: "kasan, arm64: reset pointer tags of vmapped stacks".
- New patch: "kasan, vmalloc: don't tag executable vmalloc allocations".
- New patch: "kasan, arm64: don't tag executable vmalloc allocations".
- Allowing enabling KASAN_VMALLOC with SW/HW_TAGS is moved to
"kasan: allow enabling KASAN_VMALLOC and SW/HW_TAGS", as this can only
be done once executable allocations are no longer tagged.
- Minor fixes, see patches for lists of changes.

Changes in v1->v2:
- Move memory init for vmalloc() into vmalloc code for HW_TAGS KASAN.
- Minor fixes and code reshuffling, see patches for lists of changes.


Andrey Konovalov (38):
kasan, page_alloc: deduplicate should_skip_kasan_poison
kasan, page_alloc: move tag_clear_highpage out of
kasan, page_alloc: merge kasan_free_pages into free_pages_prepare
kasan, page_alloc: simplify kasan_poison_pages call site
kasan, page_alloc: init memory of skipped pages on free
kasan: drop skip_kasan_poison variable in free_pages_prepare
mm: clarify __GFP_ZEROTAGS comment
kasan: only apply __GFP_ZEROTAGS when memory is zeroed
kasan, page_alloc: refactor init checks in post_alloc_hook
kasan, page_alloc: merge kasan_alloc_pages into post_alloc_hook
kasan, page_alloc: combine tag_clear_highpage calls in post_alloc_hook
kasan, page_alloc: move SetPageSkipKASanPoison in post_alloc_hook
kasan, page_alloc: move kernel_init_free_pages in post_alloc_hook
kasan, page_alloc: simplify kasan_unpoison_pages call site
kasan: clean up metadata byte definitions
kasan, x86, arm64, s390: rename functions for modules shadow
kasan, vmalloc: drop outdated VM_KASAN comment
kasan: reorder vmalloc hooks
kasan: add wrappers for vmalloc hooks
kasan, vmalloc: reset tags in vmalloc functions
kasan, fork: reset pointer tags of vmapped stacks
kasan, arm64: reset pointer tags of vmapped stacks
kasan, vmalloc: add vmalloc tagging for SW_TAGS
kasan, vmalloc, arm64: mark vmalloc mappings as pgprot_tagged
kasan, vmalloc: don't unpoison VM_ALLOC pages before mapping
kasan, page_alloc: allow skipping unpoisoning for HW_TAGS
kasan, page_alloc: allow skipping memory init for HW_TAGS
kasan, vmalloc: add vmalloc tagging for HW_TAGS
kasan, vmalloc: don't tag executable vmalloc allocations
kasan, arm64: don't tag executable vmalloc allocations
kasan: mark kasan_arg_stacktrace as __initdata
kasan: simplify kasan_init_hw_tags
kasan: add kasan.vmalloc command line flag
kasan: allow enabling KASAN_VMALLOC and SW/HW_TAGS
arm64: select KASAN_VMALLOC for SW/HW_TAGS modes
kasan: documentation updates
kasan: improve vmalloc tests

Documentation/dev-tools/kasan.rst | 17 ++-
arch/arm64/Kconfig | 2 +-
arch/arm64/include/asm/vmalloc.h | 10 ++
arch/arm64/include/asm/vmap_stack.h | 5 +-
arch/arm64/kernel/module.c | 5 +-
arch/arm64/net/bpf_jit_comp.c | 3 +-
arch/s390/kernel/module.c | 2 +-
arch/x86/kernel/module.c | 2 +-
include/linux/gfp.h | 28 +++--
include/linux/kasan.h | 97 +++++++++------
include/linux/vmalloc.h | 18 ++-
kernel/fork.c | 1 +
kernel/scs.c | 4 +-
lib/Kconfig.kasan | 20 +--
lib/test_kasan.c | 181 +++++++++++++++++++++++++++-
mm/kasan/common.c | 4 +-
mm/kasan/hw_tags.c | 166 ++++++++++++++++++++-----
mm/kasan/kasan.h | 16 ++-
mm/kasan/shadow.c | 63 ++++++----
mm/page_alloc.c | 150 +++++++++++++++--------
mm/vmalloc.c | 78 ++++++++++--
21 files changed, 668 insertions(+), 204 deletions(-)


 \ /
  Last update: 2021-12-13 22:52    [W:0.172 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site