[PATCH 0/3] arm64: kasan: support CONFIG_KASAN_VMALLOC

From: Lecopzer Chen
Date: Sun Jan 03 2021 - 12:13:38 EST


Linux supports KAsan for VMALLOC since commit 3c5c3cfb9ef4da9
("kasan: support backing vmalloc space with real shadow memory")

Acroding to how x86 ported it [1], they early allocated p4d and pgd,
but in arm64 I just simulate how KAsan supports MODULES_VADDR in arm64
by not to populate the vmalloc area except for kimg address.

Test environment:
4G and 8G Qemu virt,
39-bit VA + 4k PAGE_SIZE with 3-level page table,
test by lib/test_kasan.ko and lib/test_kasan_module.ko

It also works in Kaslr with CONFIG_RANDOMIZE_MODULE_REGION_FULL,
but not test for HW_TAG(I have no proper device), thus keep
HW_TAG and KASAN_VMALLOC mutual exclusion until confirming
the functionality.


[1]: commit 0609ae011deb41c ("x86/kasan: support KASAN_VMALLOC")

Signed-off-by: Lecopzer Chen <lecopzer.chen@xxxxxxxxxxxx>


Lecopzer Chen (3):
arm64: kasan: don't populate vmalloc area for CONFIG_KASAN_VMALLOC
arm64: kasan: abstract _text and _end to KERNEL_START/END
arm64: Kconfig: support CONFIG_KASAN_VMALLOC

arch/arm64/Kconfig | 1 +
arch/arm64/mm/kasan_init.c | 29 +++++++++++++++++++++--------
2 files changed, 22 insertions(+), 8 deletions(-)

--
2.25.1