From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Subject: arm64: kasan: add arch layer for memory tagging helpers This patch add a set of arch_*() memory tagging helpers currently only defined for arm64 when hardware tag-based KASAN is enabled. These helpers will be used by KASAN runtime to implement the hardware tag-based mode. The arch-level indirection level is introduced to simplify adding hardware tag-based KASAN support for other architectures in the future by defining the appropriate arch_*() macros. Link: https://lkml.kernel.org/r/fc9e5bb71201c03131a2fc00a74125723568dda9.1606161801.git.andreyknvl@xxxxxxxxxx Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Co-developed-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx> Tested-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Branislav Rankov <Branislav.Rankov@xxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Evgenii Stepanov <eugenis@xxxxxxxxxx> Cc: Kevin Brodsky <kevin.brodsky@xxxxxxx> Cc: Marco Elver <elver@xxxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm64/include/asm/memory.h | 9 +++++++++ mm/kasan/kasan.h | 26 ++++++++++++++++++++++++++ 2 files changed, 35 insertions(+) --- a/arch/arm64/include/asm/memory.h~arm64-kasan-add-arch-layer-for-memory-tagging-helpers +++ a/arch/arm64/include/asm/memory.h @@ -230,6 +230,15 @@ static inline const void *__tag_set(cons return (const void *)(__addr | __tag_shifted(tag)); } +#ifdef CONFIG_KASAN_HW_TAGS +#define arch_enable_tagging() mte_enable_kernel() +#define arch_init_tags(max_tag) mte_init_tags(max_tag) +#define arch_get_random_tag() mte_get_random_tag() +#define arch_get_mem_tag(addr) mte_get_mem_tag(addr) +#define arch_set_mem_tag_range(addr, size, tag) \ + mte_set_mem_tag_range((addr), (size), (tag)) +#endif /* CONFIG_KASAN_HW_TAGS */ + /* * Physical vs virtual RAM address space conversion. These are * private definitions which should NOT be used outside memory.h --- a/mm/kasan/kasan.h~arm64-kasan-add-arch-layer-for-memory-tagging-helpers +++ a/mm/kasan/kasan.h @@ -243,6 +243,32 @@ static inline const void *arch_kasan_set #define reset_tag(addr) ((void *)arch_kasan_reset_tag(addr)) #define get_tag(addr) arch_kasan_get_tag(addr) +#ifdef CONFIG_KASAN_HW_TAGS + +#ifndef arch_enable_tagging +#define arch_enable_tagging() +#endif +#ifndef arch_init_tags +#define arch_init_tags(max_tag) +#endif +#ifndef arch_get_random_tag +#define arch_get_random_tag() (0xFF) +#endif +#ifndef arch_get_mem_tag +#define arch_get_mem_tag(addr) (0xFF) +#endif +#ifndef arch_set_mem_tag_range +#define arch_set_mem_tag_range(addr, size, tag) ((void *)(addr)) +#endif + +#define hw_enable_tagging() arch_enable_tagging() +#define hw_init_tags(max_tag) arch_init_tags(max_tag) +#define hw_get_random_tag() arch_get_random_tag() +#define hw_get_mem_tag(addr) arch_get_mem_tag(addr) +#define hw_set_mem_tag_range(addr, size, tag) arch_set_mem_tag_range((addr), (size), (tag)) + +#endif /* CONFIG_KASAN_HW_TAGS */ + /* * Exported functions for interfaces called from assembly or from generated * code. Declarations here to avoid warning about missing declarations. _
