| Message ID | 20210206083552.24394-1-lecopzer.chen@mediatek.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | arm64: kasan: support CONFIG_KASAN_VMALLOC | expand |
Hi Lecopzer, On Sat, Feb 06, 2021 at 04:35:47PM +0800, Lecopzer Chen wrote: > 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. Do you plan an update to a newer kernel like 5.12-rc3? > Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com> > Acked-by: Andrey Konovalov <andreyknvl@google.com> > Tested-by: Andrey Konovalov <andreyknvl@google.com> > Tested-by: Ard Biesheuvel <ardb@kernel.org> You could move these to individual patches rather than the cover letter, assuming that they still stand after the changes you've made. Also note that Andrey K no longer has the @google.com email address if you cc him on future patches (replace it with @gmail.com). Thanks.
On Sat, Mar 20, 2021 at 1:41 AM Catalin Marinas <catalin.marinas@arm.com> wrote: > > Hi Lecopzer, > > On Sat, Feb 06, 2021 at 04:35:47PM +0800, Lecopzer Chen wrote: > > 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. > > Do you plan an update to a newer kernel like 5.12-rc3? > Yes, of course. I dealt with some personal matters so didn't update these series last month. > > Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com> > > Acked-by: Andrey Konovalov <andreyknvl@google.com> > > Tested-by: Andrey Konovalov <andreyknvl@google.com> > > Tested-by: Ard Biesheuvel <ardb@kernel.org> > > You could move these to individual patches rather than the cover letter, > assuming that they still stand after the changes you've made. Also note > that Andrey K no longer has the @google.com email address if you cc him > on future patches (replace it with @gmail.com). > Ok thanks for the suggestion. I will move them to each patch and correct the email address. Thanks, Lecopzer
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. ----------- vmalloc_shadow_start | | | | | | <= non-mapping | | | | |-----------| |///////////|<- kimage shadow with page table mapping. |-----------| | | | | <= non-mapping | | ------------- vmalloc_shadow_end |00000000000| |00000000000| <= Zero shadow |00000000000| ------------- KASAN_SHADOW_END 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 works in Kaslr with CONFIG_RANDOMIZE_MODULE_REGION_FULL and randomize module region inside vmalloc area. Also work with VMAP_STACK, thanks Ard for testing it. [1]: commit 0609ae011deb41c ("x86/kasan: support KASAN_VMALLOC") Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com> Acked-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Ard Biesheuvel <ardb@kernel.org> --- Thanks Will Deacon, Ard Biesheuvel and Andrey Konovalov for reviewing and suggestion. v3 -> v2 rebase on 5.11-rc6 1. remove always true condition in kasan_init() and remove unsed vmalloc_shadow_start. 2. select KASAN_VMALLOC if KANSAN_GENERIC is enabled for VMAP_STACK. 3. tweak commit message v2 -> v1 1. kasan_init.c tweak indent 2. change Kconfig depends only on HAVE_ARCH_KASAN 3. support randomized module region. v2: https://lkml.org/lkml/2021/1/9/49 v1: https://lore.kernel.org/lkml/20210103171137.153834-1-lecopzer@gmail.com/ --- Lecopzer Chen (5): 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 arm64: kaslr: support randomized module area with KASAN_VMALLOC arm64: Kconfig: select KASAN_VMALLOC if KANSAN_GENERIC is enabled arch/arm64/Kconfig | 2 ++ arch/arm64/kernel/kaslr.c | 18 ++++++++++-------- arch/arm64/kernel/module.c | 16 +++++++++------- arch/arm64/mm/kasan_init.c | 24 ++++++++++++++++-------- 4 files changed, 37 insertions(+), 23 deletions(-)