From patchwork Thu Jan 7 17:29:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincenzo Frascino X-Patchwork-Id: 12004563 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=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 81106C433DB for ; Thu, 7 Jan 2021 17:31:52 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4029022C9F for ; Thu, 7 Jan 2021 17:31:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4029022C9F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=l1i1ZeLEw29jcMUbndzvkv7au1g9X3yTBOMKT0pBENg=; b=C1ZGjYuqJoIduNUFjh9XkYYPV FN9tTSxxNEA0DUBdoUp07KJJydBcKHVFOdJNtIT5Y/PfSvf5hUhNuTb25EiA4idy/cswRTU1lAxu6 iMYbXFd9RTLTbFKZOYH5ZZqdia82wvoiH4gjoxA8floWClcMJEshvFTIoLMCnrMpWJ34lawprTusc v7Ed7K1jg+vFNmdvMUgTn2/+QCBVrm5XaHPu7CbGBB+WutzPTVXteKrQjeVzRyky8187hljBKModE no7HAymmFqiNj/KLma83LM5I+5R4IPs+HByFBxLNDXvN7g2DKZFjzHWI/Us7vmUjvaKYaJ7I5Am9y EKl92Dc+w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kxZ7L-0005KX-E6; Thu, 07 Jan 2021 17:30:35 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kxZ7D-0005Iy-Iw for linux-arm-kernel@lists.infradead.org; Thu, 07 Jan 2021 17:30:28 +0000 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 A4EE0ED1; Thu, 7 Jan 2021 09:30:22 -0800 (PST) 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 EAA443F719; Thu, 7 Jan 2021 09:30:20 -0800 (PST) From: Vincenzo Frascino To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com Subject: [PATCH v2 1/4] kasan, arm64: Add KASAN light mode Date: Thu, 7 Jan 2021 17:29:05 +0000 Message-Id: <20210107172908.42686-2-vincenzo.frascino@arm.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210107172908.42686-1-vincenzo.frascino@arm.com> References: <20210107172908.42686-1-vincenzo.frascino@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210107_123027_785990_BBA106D2 X-CRM114-Status: GOOD ( 22.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marco Elver , Catalin Marinas , Branislav Rankov , Alexander Potapenko , Evgenii Stepanov , Andrey Konovalov , Andrey Ryabinin , Vincenzo Frascino , Will Deacon , Dmitry Vyukov Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Architectures supported by KASAN HW can provide a light mode of execution. On an MTE enabled arm64 hw for example this can be identified with the asynch mode of execution. If an async exception occurs, the arm64 core updates a register which is asynchronously detected the next time in which the kernel is accessed. KASAN requires a specific mode of execution to make use of this hw feature. Add KASAN HW light execution mode. Note: This patch adds the KASAN_ARG_MODE_LIGHT config option and the "light" kernel command line option to enable the described feature. This patch introduces the kasan_def.h header to make easier to propagate the relevant enumerations to the architectural code. Cc: Dmitry Vyukov Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Andrey Konovalov Signed-off-by: Vincenzo Frascino --- arch/arm64/include/asm/memory.h | 2 +- arch/arm64/include/asm/mte-kasan.h | 5 +++-- arch/arm64/kernel/mte.c | 2 +- include/linux/kasan.h | 1 + include/linux/kasan_def.h | 25 +++++++++++++++++++++++++ mm/kasan/hw_tags.c | 24 ++++-------------------- mm/kasan/kasan.h | 2 +- 7 files changed, 36 insertions(+), 25 deletions(-) create mode 100644 include/linux/kasan_def.h diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 18fce223b67b..3a7c5beb7096 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -231,7 +231,7 @@ static inline const void *__tag_set(const void *addr, u8 tag) } #ifdef CONFIG_KASAN_HW_TAGS -#define arch_enable_tagging() mte_enable_kernel() +#define arch_enable_tagging(mode) mte_enable_kernel(mode) #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/arch/arm64/include/asm/mte-kasan.h b/arch/arm64/include/asm/mte-kasan.h index 26349a4b5e2e..79e612c31186 100644 --- a/arch/arm64/include/asm/mte-kasan.h +++ b/arch/arm64/include/asm/mte-kasan.h @@ -9,6 +9,7 @@ #ifndef __ASSEMBLY__ +#include #include /* @@ -29,7 +30,7 @@ u8 mte_get_mem_tag(void *addr); u8 mte_get_random_tag(void); void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag); -void mte_enable_kernel(void); +void mte_enable_kernel(enum kasan_arg_mode mode); void mte_init_tags(u64 max_tag); #else /* CONFIG_ARM64_MTE */ @@ -52,7 +53,7 @@ static inline void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag) return addr; } -static inline void mte_enable_kernel(void) +static inline void mte_enable_kernel(enum kasan_arg_mode mode) { } diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c index dc9ada64feed..24a273d47df1 100644 --- a/arch/arm64/kernel/mte.c +++ b/arch/arm64/kernel/mte.c @@ -151,7 +151,7 @@ void mte_init_tags(u64 max_tag) write_sysreg_s(SYS_GCR_EL1_RRND | gcr_kernel_excl, SYS_GCR_EL1); } -void mte_enable_kernel(void) +void mte_enable_kernel(enum kasan_arg_mode mode) { /* Enable MTE Sync Mode for EL1. */ sysreg_clear_set(sctlr_el1, SCTLR_ELx_TCF_MASK, SCTLR_ELx_TCF_SYNC); diff --git a/include/linux/kasan.h b/include/linux/kasan.h index 5e0655fb2a6f..026031444217 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -2,6 +2,7 @@ #ifndef _LINUX_KASAN_H #define _LINUX_KASAN_H +#include #include #include diff --git a/include/linux/kasan_def.h b/include/linux/kasan_def.h new file mode 100644 index 000000000000..e774b0122980 --- /dev/null +++ b/include/linux/kasan_def.h @@ -0,0 +1,25 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_KASAN_DEF_H +#define _LINUX_KASAN_DEF_H + +enum kasan_arg_mode { + KASAN_ARG_MODE_DEFAULT, + KASAN_ARG_MODE_OFF, + KASAN_ARG_MODE_LIGHT, + KASAN_ARG_MODE_PROD, + KASAN_ARG_MODE_FULL, +}; + +enum kasan_arg_stacktrace { + KASAN_ARG_STACKTRACE_DEFAULT, + KASAN_ARG_STACKTRACE_OFF, + KASAN_ARG_STACKTRACE_ON, +}; + +enum kasan_arg_fault { + KASAN_ARG_FAULT_DEFAULT, + KASAN_ARG_FAULT_REPORT, + KASAN_ARG_FAULT_PANIC, +}; + +#endif /* _LINUX_KASAN_DEF_H */ diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c index 55bd6f09c70f..d5c6ad8b2c44 100644 --- a/mm/kasan/hw_tags.c +++ b/mm/kasan/hw_tags.c @@ -19,25 +19,6 @@ #include "kasan.h" -enum kasan_arg_mode { - KASAN_ARG_MODE_DEFAULT, - KASAN_ARG_MODE_OFF, - KASAN_ARG_MODE_PROD, - KASAN_ARG_MODE_FULL, -}; - -enum kasan_arg_stacktrace { - KASAN_ARG_STACKTRACE_DEFAULT, - KASAN_ARG_STACKTRACE_OFF, - KASAN_ARG_STACKTRACE_ON, -}; - -enum kasan_arg_fault { - KASAN_ARG_FAULT_DEFAULT, - KASAN_ARG_FAULT_REPORT, - KASAN_ARG_FAULT_PANIC, -}; - static enum kasan_arg_mode kasan_arg_mode __ro_after_init; static enum kasan_arg_stacktrace kasan_arg_stacktrace __ro_after_init; static enum kasan_arg_fault kasan_arg_fault __ro_after_init; @@ -60,6 +41,8 @@ static int __init early_kasan_mode(char *arg) if (!strcmp(arg, "off")) kasan_arg_mode = KASAN_ARG_MODE_OFF; + else if (!strcmp(arg, "light")) + kasan_arg_mode = KASAN_ARG_MODE_LIGHT; else if (!strcmp(arg, "prod")) kasan_arg_mode = KASAN_ARG_MODE_PROD; else if (!strcmp(arg, "full")) @@ -118,7 +101,7 @@ void kasan_init_hw_tags_cpu(void) return; hw_init_tags(KASAN_TAG_MAX); - hw_enable_tagging(); + hw_enable_tagging(kasan_arg_mode); } /* kasan_init_hw_tags() is called once on boot CPU. */ @@ -145,6 +128,7 @@ void __init kasan_init_hw_tags(void) case KASAN_ARG_MODE_OFF: /* If KASAN is disabled, do nothing. */ return; + case KASAN_ARG_MODE_LIGHT: case KASAN_ARG_MODE_PROD: static_branch_enable(&kasan_flag_enabled); break; diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index cc4d9e1d49b1..78c09279327e 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -284,7 +284,7 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) #define arch_set_mem_tag_range(addr, size, tag) ((void *)(addr)) #endif -#define hw_enable_tagging() arch_enable_tagging() +#define hw_enable_tagging(mode) arch_enable_tagging(mode) #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)