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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 2AB37C63777 for ; Mon, 30 Nov 2020 23:35:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF3E320725 for ; Mon, 30 Nov 2020 23:35:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="OP+NuPPV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389038AbgK3Xfb (ORCPT ); Mon, 30 Nov 2020 18:35:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388692AbgK3Xfa (ORCPT ); Mon, 30 Nov 2020 18:35:30 -0500 Received: from mail-qv1-xf49.google.com (mail-qv1-xf49.google.com [IPv6:2607:f8b0:4864:20::f49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 95382C0613D3 for ; Mon, 30 Nov 2020 15:34:50 -0800 (PST) Received: by mail-qv1-xf49.google.com with SMTP id t14so8691643qvc.13 for ; Mon, 30 Nov 2020 15:34:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=/2hpXChav6Wt/RpcbVyRVD6Lx6UtoR7/piGzUBFcDPA=; b=OP+NuPPVKjRdl73IZILK5SqdKD4Ht7FixlV8PA26OKMxjg6NUNaSCQQQNc2lbAac3K h1tLLOXfkP/uccCUDN2SRKeBbQpAO+m37Klbfs/YBX/ltEAXIEW77i0UKV8LrGlsqf2P /+/faMrqoARnijNtjnwAmwoQZrRUIUzPQgd9vtZuj1FUXhFPNYgyDCtZsZWCaGVGtJ+r FcenFt6d6RLzZSF1mSI2tM1UcswgM+eAdr/lLCacaYgd2GRf49kp5rjwcBwr6xmdqBoX 5xL/srF1pLiVrDoS78yuk0GSdP8R+Sx7/7/VmEU+GUgdKsbDDb+hLlU1rii1VPQtX71/ xaZQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=/2hpXChav6Wt/RpcbVyRVD6Lx6UtoR7/piGzUBFcDPA=; b=BAuPFUUUc8dnPAAilMM95XgEkWLrzItsovLWyNvZke7Ef98mRmcwzyKP0BMZGgeSkJ vYjqwaZB1lkPUtSW3vlWABTQm8wHS5Th7kl2jV92Lf5oOzOtA/kMNxjH1jhH4shBmL/+ MQ2EaZq/0vhfzJTqiY23gwUQ5FGuYYqx04L7KrraDbL7UMeuVtURLhTzwKH9q84BKKSD 1JHCtszrtWtvZ4wYnMBJzGXNwAxgoPn31Fmf8mX88tWOn9FTGl+CJHsT99w7nTVY1DX6 IQGE+OrxcYkFlNHgeI0raetuqdTlUz3ZP1Jx9HRmcOk/Ubsq46rJzw+XXd637rMmp2sO NwLw== X-Gm-Message-State: AOAM532VdqcN7Xe+6OpqJCdFBMD3kjgkB8RZ9m96SPM+h2lUBqvT6/kc CYI6k1frvzEmk5n7FpIPVke1vAufXJikLnYk7Ew= X-Google-Smtp-Source: ABdhPJwHdvyygNPpCKDDdCrsa4Ck+vRg8Gp4MXUT40WxgVL9b6BDd+oHfOski3MhrYW0e3f5GXiTcQzqE8SrmlXMELQ= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a0c:e6e7:: with SMTP id m7mr233889qvn.11.1606779289826; Mon, 30 Nov 2020 15:34:49 -0800 (PST) Date: Mon, 30 Nov 2020 15:34:42 -0800 In-Reply-To: <20201130233442.2562064-1-samitolvanen@google.com> Message-Id: <20201130233442.2562064-3-samitolvanen@google.com> Mime-Version: 1.0 References: <20201130233442.2562064-1-samitolvanen@google.com> X-Mailer: git-send-email 2.29.2.454.gaff20da3a2-goog Subject: [PATCH v3 2/2] arm64: scs: use vmapped IRQ and SDEI shadow stacks From: Sami Tolvanen To: Will Deacon , Catalin Marinas Cc: Mark Rutland , James Morse , Ard Biesheuvel , Kees Cook , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use scs_alloc() to allocate also IRQ and SDEI shadow stacks instead of using statically allocated stacks. Signed-off-by: Sami Tolvanen Acked-by: Will Deacon --- arch/arm64/kernel/Makefile | 1 - arch/arm64/kernel/entry.S | 6 ++-- arch/arm64/kernel/irq.c | 19 +++++++++++ arch/arm64/kernel/scs.c | 16 --------- arch/arm64/kernel/sdei.c | 70 ++++++++++++++++++++++++++++++++++++++ include/linux/scs.h | 4 --- 6 files changed, 92 insertions(+), 24 deletions(-) delete mode 100644 arch/arm64/kernel/scs.c diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index bbaf0bc4ad60..86364ab6f13f 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -58,7 +58,6 @@ obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_CRASH_CORE) += crash_core.o obj-$(CONFIG_ARM_SDE_INTERFACE) += sdei.o obj-$(CONFIG_ARM64_PTR_AUTH) += pointer_auth.o -obj-$(CONFIG_SHADOW_CALL_STACK) += scs.o obj-$(CONFIG_ARM64_MTE) += mte.o obj-y += vdso/ probes/ diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index b295fb912b12..5c2ac4b5b2da 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -441,7 +441,7 @@ SYM_CODE_END(__swpan_exit_el0) #ifdef CONFIG_SHADOW_CALL_STACK /* also switch to the irq shadow stack */ - adr_this_cpu scs_sp, irq_shadow_call_stack, x26 + ldr_this_cpu scs_sp, irq_shadow_call_stack_ptr, x26 #endif 9998: @@ -1097,9 +1097,9 @@ SYM_CODE_START(__sdei_asm_handler) #ifdef CONFIG_SHADOW_CALL_STACK /* Use a separate shadow call stack for normal and critical events */ cbnz w4, 3f - adr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_normal, tmp=x6 + ldr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_normal_ptr, tmp=x6 b 4f -3: adr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_critical, tmp=x6 +3: ldr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_critical_ptr, tmp=x6 4: #endif diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c index 9cf2fb87584a..5b7ada9d9559 100644 --- a/arch/arm64/kernel/irq.c +++ b/arch/arm64/kernel/irq.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -27,6 +28,22 @@ DEFINE_PER_CPU(struct nmi_ctx, nmi_contexts); DEFINE_PER_CPU(unsigned long *, irq_stack_ptr); + +DECLARE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr); + +#ifdef CONFIG_SHADOW_CALL_STACK +DEFINE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr); +#endif + +static void init_irq_scs(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + per_cpu(irq_shadow_call_stack_ptr, cpu) = + scs_alloc(cpu_to_node(cpu)); +} + #ifdef CONFIG_VMAP_STACK static void init_irq_stacks(void) { @@ -54,6 +71,8 @@ static void init_irq_stacks(void) void __init init_IRQ(void) { init_irq_stacks(); + if (IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) + init_irq_scs(); irqchip_init(); if (!handle_arch_irq) panic("No interrupt controller found."); diff --git a/arch/arm64/kernel/scs.c b/arch/arm64/kernel/scs.c deleted file mode 100644 index e8f7ff45dd8f..000000000000 --- a/arch/arm64/kernel/scs.c +++ /dev/null @@ -1,16 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Shadow Call Stack support. - * - * Copyright (C) 2019 Google LLC - */ - -#include -#include - -DEFINE_SCS(irq_shadow_call_stack); - -#ifdef CONFIG_ARM_SDE_INTERFACE -DEFINE_SCS(sdei_shadow_call_stack_normal); -DEFINE_SCS(sdei_shadow_call_stack_critical); -#endif diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c index 7689f2031c0c..d12fd786b267 100644 --- a/arch/arm64/kernel/sdei.c +++ b/arch/arm64/kernel/sdei.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include @@ -37,6 +38,14 @@ DEFINE_PER_CPU(unsigned long *, sdei_stack_normal_ptr); DEFINE_PER_CPU(unsigned long *, sdei_stack_critical_ptr); #endif +DECLARE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr); +DECLARE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr); + +#ifdef CONFIG_SHADOW_CALL_STACK +DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr); +DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr); +#endif + static void _free_sdei_stack(unsigned long * __percpu *ptr, int cpu) { unsigned long *p; @@ -90,6 +99,59 @@ static int init_sdei_stacks(void) return err; } +static void _free_sdei_scs(unsigned long * __percpu *ptr, int cpu) +{ + void *s; + + s = per_cpu(*ptr, cpu); + if (s) { + per_cpu(*ptr, cpu) = NULL; + scs_free(s); + } +} + +static void free_sdei_scs(void) +{ + int cpu; + + for_each_possible_cpu(cpu) { + _free_sdei_scs(&sdei_shadow_call_stack_normal_ptr, cpu); + _free_sdei_scs(&sdei_shadow_call_stack_critical_ptr, cpu); + } +} + +static int _init_sdei_scs(unsigned long * __percpu *ptr, int cpu) +{ + void *s; + + s = scs_alloc(cpu_to_node(cpu)); + if (!s) + return -ENOMEM; + per_cpu(*ptr, cpu) = s; + + return 0; +} + +static int init_sdei_scs(void) +{ + int cpu; + int err = 0; + + for_each_possible_cpu(cpu) { + err = _init_sdei_scs(&sdei_shadow_call_stack_normal_ptr, cpu); + if (err) + break; + err = _init_sdei_scs(&sdei_shadow_call_stack_critical_ptr, cpu); + if (err) + break; + } + + if (err) + free_sdei_scs(); + + return err; +} + static bool on_sdei_normal_stack(unsigned long sp, struct stack_info *info) { unsigned long low = (unsigned long)raw_cpu_read(sdei_stack_normal_ptr); @@ -138,6 +200,14 @@ unsigned long sdei_arch_get_entry_point(int conduit) return 0; } + if (IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) { + if (init_sdei_scs()) { + if (IS_ENABLED(CONFIG_VMAP_STACK)) + free_sdei_stacks(); + return 0; + } + } + sdei_exit_mode = (conduit == SMCCC_CONDUIT_HVC) ? SDEI_EXIT_HVC : SDEI_EXIT_SMC; #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 diff --git a/include/linux/scs.h b/include/linux/scs.h index 2a506c2a16f4..18122d9e17ff 100644 --- a/include/linux/scs.h +++ b/include/linux/scs.h @@ -22,10 +22,6 @@ /* An illegal pointer value to mark the end of the shadow stack. */ #define SCS_END_MAGIC (0x5f6UL + POISON_POINTER_DELTA) -/* Allocate a static per-CPU shadow stack */ -#define DEFINE_SCS(name) \ - DEFINE_PER_CPU(unsigned long [SCS_SIZE/sizeof(long)], name) \ - #define task_scs(tsk) (task_thread_info(tsk)->scs_base) #define task_scs_sp(tsk) (task_thread_info(tsk)->scs_sp) -- 2.29.2.454.gaff20da3a2-goog