diff options
| author | Lecopzer Chen <lecopzer.chen@mediatek.com> | 2021-03-24 12:05:18 +0800 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2021-03-29 12:34:00 +0100 |
| commit | 9a0732efa77418fc85b1bdc5ddee619e62f59545 (patch) | |
| tree | 6a23cfd9a3e96bd4b35662def8bc4c02b96111e9 /arch/arm64/mm | |
| parent | 1e28eed17697bcf343c6743f0028cc3b5dd88bf0 (diff) | |
arm64: kasan: don't populate vmalloc area for CONFIG_KASAN_VMALLOC
Linux support KAsan for VMALLOC since commit 3c5c3cfb9ef4da9
("kasan: support backing vmalloc space with real shadow memory")
Like how the MODULES_VADDR does now, just not to early populate
the VMALLOC_START between VMALLOC_END.
Before:
MODULE_VADDR: no mapping, no zero shadow at init
VMALLOC_VADDR: backed with zero shadow at init
After:
MODULE_VADDR: no mapping, no zero shadow at init
VMALLOC_VADDR: no mapping, no zero shadow at init
Thus the mapping will get allocated on demand by the core function
of KASAN_VMALLOC.
----------- vmalloc_shadow_start
| |
| |
| | <= non-mapping
| |
| |
|-----------|
|///////////|<- kimage shadow with page table mapping.
|-----------|
| |
| | <= non-mapping
| |
------------- vmalloc_shadow_end
|00000000000|
|00000000000| <= Zero shadow
|00000000000|
------------- KASAN_SHADOW_END
Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Acked-by: Andrey Konovalov <andreyknvl@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@gmail.com>
Tested-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20210324040522.15548-2-lecopzer.chen@mediatek.com
[catalin.marinas@arm.com: add a build check on VMALLOC_START != MODULES_END]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/kasan_init.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index d8e66c78440e..7598b0a96b64 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -214,6 +214,7 @@ static void __init kasan_init_shadow(void) { u64 kimg_shadow_start, kimg_shadow_end; u64 mod_shadow_start, mod_shadow_end; + u64 vmalloc_shadow_end; phys_addr_t pa_start, pa_end; u64 i; @@ -223,6 +224,8 @@ static void __init kasan_init_shadow(void) mod_shadow_start = (u64)kasan_mem_to_shadow((void *)MODULES_VADDR); mod_shadow_end = (u64)kasan_mem_to_shadow((void *)MODULES_END); + vmalloc_shadow_end = (u64)kasan_mem_to_shadow((void *)VMALLOC_END); + /* * We are going to perform proper setup of shadow memory. * At first we should unmap early shadow (clear_pgds() call below). @@ -241,12 +244,18 @@ static void __init kasan_init_shadow(void) kasan_populate_early_shadow(kasan_mem_to_shadow((void *)PAGE_END), (void *)mod_shadow_start); - kasan_populate_early_shadow((void *)kimg_shadow_end, - (void *)KASAN_SHADOW_END); - if (kimg_shadow_start > mod_shadow_end) - kasan_populate_early_shadow((void *)mod_shadow_end, - (void *)kimg_shadow_start); + if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) { + BUILD_BUG_ON(VMALLOC_START != MODULES_END); + kasan_populate_early_shadow((void *)vmalloc_shadow_end, + (void *)KASAN_SHADOW_END); + } else { + kasan_populate_early_shadow((void *)kimg_shadow_end, + (void *)KASAN_SHADOW_END); + if (kimg_shadow_start > mod_shadow_end) + kasan_populate_early_shadow((void *)mod_shadow_end, + (void *)kimg_shadow_start); + } for_each_mem_range(i, &pa_start, &pa_end) { void *start = (void *)__phys_to_virt(pa_start); |