Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751393AbdH1Vnz (ORCPT ); Mon, 28 Aug 2017 17:43:55 -0400 Received: from mail-pg0-f48.google.com ([74.125.83.48]:34352 "EHLO mail-pg0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751182AbdH1Vnw (ORCPT ); Mon, 28 Aug 2017 17:43:52 -0400 From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , Russell King , Ingo Molnar , Christian Borntraeger , "Peter Zijlstra (Intel)" , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, kernel-hardening@lists.openwall.com, David Windsor Subject: [PATCH v2 29/30] arm: Implement thread_struct whitelist for hardened usercopy Date: Mon, 28 Aug 2017 14:35:10 -0700 Message-Id: <1503956111-36652-30-git-send-email-keescook@chromium.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1503956111-36652-1-git-send-email-keescook@chromium.org> References: <1503956111-36652-1-git-send-email-keescook@chromium.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1472 Lines: 46 ARM does not carry FPU state in the thread structure, so it can declare no usercopy whitelist at all. Cc: Russell King Cc: Ingo Molnar Cc: Christian Borntraeger Cc: "Peter Zijlstra (Intel)" Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Kees Cook --- arch/arm/Kconfig | 1 + arch/arm/include/asm/processor.h | 7 +++++++ 2 files changed, 8 insertions(+) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index a208bfe367b5..3781f08d00fa 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -48,6 +48,7 @@ config ARM select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU select HAVE_ARCH_MMAP_RND_BITS if MMU select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT) + select HAVE_ARCH_THREAD_STRUCT_WHITELIST select HAVE_ARCH_TRACEHOOK select HAVE_ARM_SMCCC if CPU_V7 select HAVE_CBPF_JIT diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h index c3d5fc124a05..d6dc45c92ee5 100644 --- a/arch/arm/include/asm/processor.h +++ b/arch/arm/include/asm/processor.h @@ -45,6 +45,13 @@ struct thread_struct { struct debug_info debug; }; +/* Nothing needs to be usercopy-whitelisted from thread_struct. */ +static inline void arch_thread_struct_whitelist(unsigned long *offset, + unsigned long *size) +{ + *offset = *size = 0; +} + #define INIT_THREAD { } #ifdef CONFIG_MMU -- 2.7.4