From: Andrey Konovalov Date: Mon, 15 Mar 2021 13:20:19 +0000 (+0000) Subject: kasan, arm64: tests supports for HW_TAGS async mode X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=e80a76aa1a91;p=uclinux-h8%2Flinux.git kasan, arm64: tests supports for HW_TAGS async mode This change adds KASAN-KUnit tests support for the async HW_TAGS mode. In async mode, tag fault aren't being generated synchronously when a bad access happens, but are instead explicitly checked for by the kernel. As each KASAN-KUnit test expect a fault to happen before the test is over, check for faults as a part of the test handler. Acked-by: Catalin Marinas Acked-by: Andrey Konovalov Tested-by: Andrey Konovalov Signed-off-by: Andrey Konovalov Signed-off-by: Vincenzo Frascino Link: https://lore.kernel.org/r/20210315132019.33202-10-vincenzo.frascino@arm.com Signed-off-by: Catalin Marinas --- diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 8b0beaedbe1f..b943879c1c24 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -246,6 +246,7 @@ static inline const void *__tag_set(const void *addr, u8 tag) #define arch_enable_tagging_sync() mte_enable_kernel_sync() #define arch_enable_tagging_async() mte_enable_kernel_async() #define arch_set_tagging_report_once(state) mte_set_report_once(state) +#define arch_force_async_tag_fault() mte_check_tfsr_exit() #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) diff --git a/lib/test_kasan.c b/lib/test_kasan.c index 479c31a5dc21..785e724ce0d8 100644 --- a/lib/test_kasan.c +++ b/lib/test_kasan.c @@ -69,10 +69,10 @@ static void kasan_test_exit(struct kunit *test) * resource named "kasan_data". Do not use this name for KUnit resources * outside of KASAN tests. * - * For hardware tag-based KASAN, when a tag fault happens, tag checking is - * normally auto-disabled. When this happens, this test handler reenables - * tag checking. As tag checking can be only disabled or enabled per CPU, this - * handler disables migration (preemption). + * For hardware tag-based KASAN in sync mode, when a tag fault happens, tag + * checking is auto-disabled. When this happens, this test handler reenables + * tag checking. As tag checking can be only disabled or enabled per CPU, + * this handler disables migration (preemption). * * Since the compiler doesn't see that the expression can change the fail_data * fields, it can reorder or optimize away the accesses to those fields. @@ -80,7 +80,8 @@ static void kasan_test_exit(struct kunit *test) * expression to prevent that. */ #define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \ - if (IS_ENABLED(CONFIG_KASAN_HW_TAGS)) \ + if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ + !kasan_async_mode_enabled()) \ migrate_disable(); \ WRITE_ONCE(fail_data.report_expected, true); \ WRITE_ONCE(fail_data.report_found, false); \ @@ -92,10 +93,14 @@ static void kasan_test_exit(struct kunit *test) barrier(); \ expression; \ barrier(); \ + if (kasan_async_mode_enabled()) \ + kasan_force_async_fault(); \ + barrier(); \ KUNIT_EXPECT_EQ(test, \ READ_ONCE(fail_data.report_expected), \ READ_ONCE(fail_data.report_found)); \ - if (IS_ENABLED(CONFIG_KASAN_HW_TAGS)) { \ + if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ + !kasan_async_mode_enabled()) { \ if (READ_ONCE(fail_data.report_found)) \ kasan_enable_tagging_sync(); \ migrate_enable(); \ diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c index 1df4ce803861..4004388b4e4b 100644 --- a/mm/kasan/hw_tags.c +++ b/mm/kasan/hw_tags.c @@ -252,4 +252,10 @@ void kasan_enable_tagging_sync(void) } EXPORT_SYMBOL_GPL(kasan_enable_tagging_sync); +void kasan_force_async_fault(void) +{ + hw_force_async_tag_fault(); +} +EXPORT_SYMBOL_GPL(kasan_force_async_fault); + #endif diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index 02e9656b857f..2d29069ae977 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -304,6 +304,9 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) #ifndef arch_set_tagging_report_once #define arch_set_tagging_report_once(state) #endif +#ifndef arch_force_async_tag_fault +#define arch_force_async_tag_fault() +#endif #ifndef arch_get_random_tag #define arch_get_random_tag() (0xFF) #endif @@ -318,6 +321,7 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) #define hw_enable_tagging_async() arch_enable_tagging_async() #define hw_init_tags(max_tag) arch_init_tags(max_tag) #define hw_set_tagging_report_once(state) arch_set_tagging_report_once(state) +#define hw_force_async_tag_fault() arch_force_async_tag_fault() #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)) @@ -334,11 +338,13 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) void kasan_set_tagging_report_once(bool state); void kasan_enable_tagging_sync(void); +void kasan_force_async_fault(void); #else /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */ static inline void kasan_set_tagging_report_once(bool state) { } static inline void kasan_enable_tagging_sync(void) { } +static inline void kasan_force_async_fault(void) { } #endif /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */ diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 8b0843a2cdd7..14bd51ea2348 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -366,6 +366,11 @@ void kasan_report_async(void) { unsigned long flags; +#if IS_ENABLED(CONFIG_KUNIT) + if (current->kunit_test) + kasan_update_kunit_status(current->kunit_test); +#endif /* IS_ENABLED(CONFIG_KUNIT) */ + start_report(&flags); pr_err("BUG: KASAN: invalid-access\n"); pr_err("Asynchronous mode enabled: no access details available\n");