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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 D8B00ECDFB8 for ; Thu, 19 Jul 2018 23:28:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B71F2084C for ; Thu, 19 Jul 2018 23:28:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8B71F2084C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731505AbeGTANm (ORCPT ); Thu, 19 Jul 2018 20:13:42 -0400 Received: from mail-qt0-f194.google.com ([209.85.216.194]:38843 "EHLO mail-qt0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731398AbeGTANl (ORCPT ); Thu, 19 Jul 2018 20:13:41 -0400 Received: by mail-qt0-f194.google.com with SMTP id y19-v6so8796441qto.5 for ; Thu, 19 Jul 2018 16:28:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=gN8QL/Y11A7E6FhcHbLbCidBJaN3nqe2yD2uQB8Up3Q=; b=rEwunnlTBAOB1IRIUrhbgKkxwPw+rOTTxqpx76dLYyP5DRnf9bKME2Sld+aYOdvDar OP+7P584r4+v7JjHl22JSZPTL62aZS2RSkbX6rkje/yDcrvdGREzx7kzuPGLY1N0AtcI 70JPEx1IDEKg9y0SUt+Ss/xDRYmHW3YyoF5UNwhrgxMRD5hsDwbz/ASgh3fPr5C8jO8S +9qvfT1GaPfEXIGir+lXEqiilCN0VDWHIKf4pEvSObTRwGjOkpPHdzgHxA/k3ypwzHGF VTo8K8EJS9NifmQ80APRu/XaC7lJnvg77Vj6EODXo8igebGuBCqGA/IpAyBuZov/ouuq WFzQ== X-Gm-Message-State: AOUpUlE2ZY1lt54OmhOyGdnyGqS956RwpIRCcnM4n6fuMkQkAytS04jj 7QnhSDHly4SJHEvG6Y4Iynm6Gw== X-Google-Smtp-Source: AAOMgpeENeJlWCbP9LStrn6WbJsxLuOQmabTiD2Wpd5UEKVOSqTSuEMDpYJcOE6qksHsR0zQRWMRbg== X-Received: by 2002:a0c:d8d8:: with SMTP id w24-v6mr7599521qvj.49.1532042898149; Thu, 19 Jul 2018 16:28:18 -0700 (PDT) Received: from labbott-redhat.redhat.com ([2601:602:9802:a8dc:4eb2:6dae:ab32:e5b0]) by smtp.gmail.com with ESMTPSA id f70-v6sm258205qke.77.2018.07.19.16.28.15 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 19 Jul 2018 16:28:17 -0700 (PDT) From: Laura Abbott To: Alexander Popov , Kees Cook , Mark Rutland , Ard Biesheuvel Cc: Laura Abbott , kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Will Deacon , Catalin Marinas Subject: [PATCHv2 2/2] arm64: Clear the stack Date: Thu, 19 Jul 2018 16:28:06 -0700 Message-Id: <20180719232806.3397-3-labbott@redhat.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180719232806.3397-1-labbott@redhat.com> References: <20180719232806.3397-1-labbott@redhat.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Implementation of stackleak based heavily on the x86 version Signed-off-by: Laura Abbott --- v2: Convert to adjusted on_acessible_stack APIs. Fixed alloca check to just panic. Dropped the extra include per Kees. I also didn't add the Reviewed-by since the APIs did change and I wanted another pass. --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/processor.h | 15 +++++++++++++++ arch/arm64/kernel/entry.S | 7 +++++++ arch/arm64/kernel/process.c | 17 +++++++++++++++++ arch/arm64/kvm/hyp/Makefile | 3 ++- drivers/firmware/efi/libstub/Makefile | 3 ++- 6 files changed, 44 insertions(+), 2 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 42c090cf0292..216d36a49ab5 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -96,6 +96,7 @@ config ARM64 select HAVE_ARCH_MMAP_RND_BITS select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT select HAVE_ARCH_SECCOMP_FILTER + select HAVE_ARCH_STACKLEAK select HAVE_ARCH_THREAD_STRUCT_WHITELIST select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_TRANSPARENT_HUGEPAGE diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index a73ae1e49200..0061450a793b 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -266,5 +266,20 @@ extern void __init minsigstksz_setup(void); #define SVE_SET_VL(arg) sve_set_current_vl(arg) #define SVE_GET_VL() sve_get_current_vl() +/* + * For CONFIG_GCC_PLUGIN_STACKLEAK + * + * These need to be macros because otherwise we get stuck in a nightmare + * of header definitions for the use of task_stack_page. + */ + +#define current_top_of_stack() \ +({ \ + struct stack_info _info; \ + BUG_ON(!on_accessible_stack(current, current_stack_pointer, &_info)); \ + _info.high; \ +}) +#define on_thread_stack() (on_task_stack(current, current_stack_pointer, NULL)) + #endif /* __ASSEMBLY__ */ #endif /* __ASM_PROCESSOR_H */ diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 28ad8799406f..67d12016063d 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -431,6 +431,11 @@ tsk .req x28 // current thread_info .text + .macro stackleak_erase +#ifdef CONFIG_GCC_PLUGIN_STACKLEAK + bl stackleak_erase +#endif + .endm /* * Exception vectors. */ @@ -910,6 +915,7 @@ ret_fast_syscall: and x2, x1, #_TIF_WORK_MASK cbnz x2, work_pending enable_step_tsk x1, x2 + stackleak_erase kernel_exit 0 ret_fast_syscall_trace: enable_daif @@ -936,6 +942,7 @@ ret_to_user: cbnz x2, work_pending finish_ret_to_user: enable_step_tsk x1, x2 + stackleak_erase kernel_exit 0 ENDPROC(ret_to_user) diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index e10bc363f533..2724e4d31b16 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -493,3 +493,20 @@ void arch_setup_new_exec(void) { current->mm->context.flags = is_compat_task() ? MMCF_AARCH32 : 0; } + +#ifdef CONFIG_GCC_PLUGIN_STACKLEAK +void __used stackleak_check_alloca(unsigned long size) +{ + unsigned long stack_left; + unsigned long current_sp = current_stack_pointer; + struct stack_info info; + + BUG_ON(!on_accessible_stack(current, current_sp, &info)); + + stack_left = current_sp - info.low; + + if (size >= stack_left) + panic("alloca() over the kernel stack boundary\n"); +} +EXPORT_SYMBOL(stackleak_check_alloca); +#endif diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile index 4313f7475333..2fabc2dc1966 100644 --- a/arch/arm64/kvm/hyp/Makefile +++ b/arch/arm64/kvm/hyp/Makefile @@ -3,7 +3,8 @@ # Makefile for Kernel-based Virtual Machine module, HYP part # -ccflags-y += -fno-stack-protector -DDISABLE_BRANCH_PROFILING +ccflags-y += -fno-stack-protector -DDISABLE_BRANCH_PROFILING \ + $(DISABLE_STACKLEAK_PLUGIN) KVM=../../../../virt/kvm diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index a34e9290a699..25dd2a14560d 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -20,7 +20,8 @@ cflags-$(CONFIG_EFI_ARMSTUB) += -I$(srctree)/scripts/dtc/libfdt KBUILD_CFLAGS := $(cflags-y) -DDISABLE_BRANCH_PROFILING \ -D__NO_FORTIFY \ $(call cc-option,-ffreestanding) \ - $(call cc-option,-fno-stack-protector) + $(call cc-option,-fno-stack-protector) \ + $(DISABLE_STACKLEAK_PLUGIN) GCOV_PROFILE := n KASAN_SANITIZE := n -- 2.17.1