| Message ID | ff221eca3db7a1f208c30c625b7d209fba33abb9.1515684162.git.andreyknvl@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Jan 11, 2018 at 04:29:09PM +0100, Andrey Konovalov wrote: > Right now the fact that KASAN uses a single shadow byte for 8 bytes of > memory is scattered all over the code. > > This change defines KASAN_SHADOW_SCALE_SHIFT early in asm include files > and makes use of this constant where necessary. > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com> > --- > arch/arm64/include/asm/kasan.h | 3 ++- > arch/arm64/include/asm/memory.h | 3 ++- > arch/arm64/mm/kasan_init.c | 3 ++- > arch/x86/include/asm/kasan.h | 8 ++++++-- > include/linux/kasan.h | 2 -- > 5 files changed, 12 insertions(+), 7 deletions(-) For the arm64 parts: Acked-by: Will Deacon <will.deacon@arm.com> Will
On 01/11/2018 06:29 PM, Andrey Konovalov wrote: > diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h > index e266f80e45b7..811643fe7640 100644 > --- a/arch/arm64/include/asm/kasan.h > +++ b/arch/arm64/include/asm/kasan.h > @@ -27,7 +27,8 @@ > * should satisfy the following equation: > * KASAN_SHADOW_OFFSET = KASAN_SHADOW_END - (1ULL << 61) Care to update comments as well? > */ > -#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << (64 - 3))) > +#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \ > + (64 - KASAN_SHADOW_SCALE_SHIFT))) > > void kasan_init(void); > void kasan_copy_shadow(pgd_t *pgdir);
On Thu, Jan 11, 2018 at 10:59 PM, Andrey Ryabinin <aryabinin@virtuozzo.com> wrote: > > > On 01/11/2018 06:29 PM, Andrey Konovalov wrote: > >> diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h >> index e266f80e45b7..811643fe7640 100644 >> --- a/arch/arm64/include/asm/kasan.h >> +++ b/arch/arm64/include/asm/kasan.h >> @@ -27,7 +27,8 @@ >> * should satisfy the following equation: >> * KASAN_SHADOW_OFFSET = KASAN_SHADOW_END - (1ULL << 61) > > Care to update comments as well? Sure, done in v2. > >> */ >> -#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << (64 - 3))) >> +#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \ >> + (64 - KASAN_SHADOW_SCALE_SHIFT))) >> >> void kasan_init(void); >> void kasan_copy_shadow(pgd_t *pgdir);
diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h index e266f80e45b7..811643fe7640 100644 --- a/arch/arm64/include/asm/kasan.h +++ b/arch/arm64/include/asm/kasan.h @@ -27,7 +27,8 @@ * should satisfy the following equation: * KASAN_SHADOW_OFFSET = KASAN_SHADOW_END - (1ULL << 61) */ -#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << (64 - 3))) +#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \ + (64 - KASAN_SHADOW_SCALE_SHIFT))) void kasan_init(void); void kasan_copy_shadow(pgd_t *pgdir); diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index d4bae7d6e0d8..50fa96a49792 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -85,7 +85,8 @@ * stack size when KASAN is in use. */ #ifdef CONFIG_KASAN -#define KASAN_SHADOW_SIZE (UL(1) << (VA_BITS - 3)) +#define KASAN_SHADOW_SCALE_SHIFT 3 +#define KASAN_SHADOW_SIZE (UL(1) << (VA_BITS - KASAN_SHADOW_SCALE_SHIFT)) #define KASAN_THREAD_SHIFT 1 #else #define KASAN_SHADOW_SIZE (0) diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index acba49fb5aac..6e02e6fb4c7b 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -135,7 +135,8 @@ static void __init kasan_pgd_populate(unsigned long addr, unsigned long end, /* The early shadow maps everything to a single page of zeroes */ asmlinkage void __init kasan_early_init(void) { - BUILD_BUG_ON(KASAN_SHADOW_OFFSET != KASAN_SHADOW_END - (1UL << 61)); + BUILD_BUG_ON(KASAN_SHADOW_OFFSET != + KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT))); BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PGDIR_SIZE)); BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE)); kasan_pgd_populate(KASAN_SHADOW_START, KASAN_SHADOW_END, NUMA_NO_NODE, diff --git a/arch/x86/include/asm/kasan.h b/arch/x86/include/asm/kasan.h index b577dd0916aa..737b7ea9bea3 100644 --- a/arch/x86/include/asm/kasan.h +++ b/arch/x86/include/asm/kasan.h @@ -4,6 +4,7 @@ #include <linux/const.h> #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) +#define KASAN_SHADOW_SCALE_SHIFT 3 /* * Compiler uses shadow offset assuming that addresses start @@ -12,12 +13,15 @@ * 'kernel address space start' >> KASAN_SHADOW_SCALE_SHIFT */ #define KASAN_SHADOW_START (KASAN_SHADOW_OFFSET + \ - ((-1UL << __VIRTUAL_MASK_SHIFT) >> 3)) + ((-1UL << __VIRTUAL_MASK_SHIFT) >> \ + KASAN_SHADOW_SCALE_SHIFT)) /* * 47 bits for kernel address -> (47 - 3) bits for shadow * 56 bits for kernel address -> (56 - 3) bits for shadow */ -#define KASAN_SHADOW_END (KASAN_SHADOW_START + (1ULL << (__VIRTUAL_MASK_SHIFT - 3))) +#define KASAN_SHADOW_END (KASAN_SHADOW_START + \ + (1ULL << (__VIRTUAL_MASK_SHIFT - \ + KASAN_SHADOW_SCALE_SHIFT))) #ifndef __ASSEMBLY__ diff --git a/include/linux/kasan.h b/include/linux/kasan.h index e3eb834c9a35..e9eaa964473a 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -11,8 +11,6 @@ struct task_struct; #ifdef CONFIG_KASAN -#define KASAN_SHADOW_SCALE_SHIFT 3 - #include <asm/kasan.h> #include <asm/pgtable.h>
Right now the fact that KASAN uses a single shadow byte for 8 bytes of memory is scattered all over the code. This change defines KASAN_SHADOW_SCALE_SHIFT early in asm include files and makes use of this constant where necessary. Signed-off-by: Andrey Konovalov <andreyknvl@google.com> --- arch/arm64/include/asm/kasan.h | 3 ++- arch/arm64/include/asm/memory.h | 3 ++- arch/arm64/mm/kasan_init.c | 3 ++- arch/x86/include/asm/kasan.h | 8 ++++++-- include/linux/kasan.h | 2 -- 5 files changed, 12 insertions(+), 7 deletions(-)