From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E2574C433DB for ; Mon, 15 Mar 2021 13:21:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACD5664ED2 for ; Mon, 15 Mar 2021 13:21:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230425AbhCONVW (ORCPT ); Mon, 15 Mar 2021 09:21:22 -0400 Received: from foss.arm.com ([217.140.110.172]:40018 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229960AbhCONUs (ORCPT ); Mon, 15 Mar 2021 09:20:48 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 268641474; Mon, 15 Mar 2021 06:20:48 -0700 (PDT) Received: from e119884-lin.cambridge.arm.com (e119884-lin.cambridge.arm.com [10.1.196.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 44B5B3F792; Mon, 15 Mar 2021 06:20:46 -0700 (PDT) From: Vincenzo Frascino To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com Cc: Vincenzo Frascino , Andrew Morton , Catalin Marinas , Will Deacon , Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Marco Elver , Evgenii Stepanov , Branislav Rankov , Andrey Konovalov , Lorenzo Pieralisi Subject: [PATCH v16 9/9] kasan, arm64: tests supports for HW_TAGS async mode Date: Mon, 15 Mar 2021 13:20:19 +0000 Message-Id: <20210315132019.33202-10-vincenzo.frascino@arm.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210315132019.33202-1-vincenzo.frascino@arm.com> References: <20210315132019.33202-1-vincenzo.frascino@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andrey Konovalov 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 --- arch/arm64/include/asm/memory.h | 1 + lib/test_kasan.c | 17 +++++++++++------ mm/kasan/hw_tags.c | 6 ++++++ mm/kasan/kasan.h | 6 ++++++ mm/kasan/report.c | 5 +++++ 5 files changed, 29 insertions(+), 6 deletions(-) diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index a07923eb33c5..7d0fd4f36e23 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 929fbe06b154..0882d6c17e62 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 56b155ddaf30..f34253e29b4a 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, init) \ @@ -335,11 +339,13 @@ 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"); -- 2.30.2