From patchwork Wed Nov 28 09:27:06 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe Leroy X-Patchwork-Id: 1004306 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 434b5n4y2gz9s6w for ; Wed, 28 Nov 2018 20:32:13 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=c-s.fr Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 434b5n24LbzDqZN for ; Wed, 28 Nov 2018 20:32:13 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=c-s.fr X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=c-s.fr (client-ip=93.17.236.30; helo=pegase1.c-s.fr; envelope-from=christophe.leroy@c-s.fr; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=c-s.fr Received: from pegase1.c-s.fr (pegase1.c-s.fr [93.17.236.30]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 434Zzz22J7zDqZV for ; Wed, 28 Nov 2018 20:27:10 +1100 (AEDT) Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 434Zzs6JDdz9vBKG; Wed, 28 Nov 2018 10:27:05 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id eioCN6G33gbZ; Wed, 28 Nov 2018 10:27:05 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 434Zzs5gVqz9vBK9; Wed, 28 Nov 2018 10:27:05 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id AB8878B85D; Wed, 28 Nov 2018 10:27:06 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id uIV2XMwDv7Ca; Wed, 28 Nov 2018 10:27:06 +0100 (CET) Received: from po14163vm.idsi0.si.c-s.fr (po15451.idsi0.si.c-s.fr [172.25.231.2]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 907658B853; Wed, 28 Nov 2018 10:27:06 +0100 (CET) Received: by po14163vm.idsi0.si.c-s.fr (Postfix, from userid 0) id 8851469AFA; Wed, 28 Nov 2018 09:27:06 +0000 (UTC) Message-Id: <7260e8d9a642c60d4f4db0e8b66ec485a1f474d5.1543356926.git.christophe.leroy@c-s.fr> In-Reply-To: <76d777b36e54e7b8d4c196405decc712fc5eaf45.1543356926.git.christophe.leroy@c-s.fr> References: <76d777b36e54e7b8d4c196405decc712fc5eaf45.1543356926.git.christophe.leroy@c-s.fr> From: Christophe Leroy Subject: [RFC PATCH v2 02/11] powerpc: Add framework for Kernel Userspace Protection To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , ruscur@russell.cc Date: Wed, 28 Nov 2018 09:27:06 +0000 (UTC) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" This patch adds a skeleton for Kernel Userspace Protection functionnalities like Kernel Userspace Access Protection and Kernel Userspace Execution Prevention The subsequent implementation of KUAP for radix makes use of a MMU feature in order to patch out assembly when KUAP is disabled or unsupported. This won't work unless there's an entry point for KUP support before the feature magic happens, so for PPC64 setup_kup() is called early in setup. On PPC32, feature_fixup is done too early to allow the same. Suggested-by: Russell Currey Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/kup.h | 11 +++++++++++ arch/powerpc/kernel/setup_64.c | 7 +++++++ arch/powerpc/mm/init-common.c | 5 +++++ arch/powerpc/mm/init_32.c | 3 +++ 4 files changed, 26 insertions(+) create mode 100644 arch/powerpc/include/asm/kup.h diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h new file mode 100644 index 000000000000..7a88b8b9b54d --- /dev/null +++ b/arch/powerpc/include/asm/kup.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_KUP_H_ +#define _ASM_POWERPC_KUP_H_ + +#ifndef __ASSEMBLY__ + +void setup_kup(void); + +#endif /* !__ASSEMBLY__ */ + +#endif /* _ASM_POWERPC_KUP_H_ */ diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 236c1151a3a7..771f280a6bf6 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -68,6 +68,7 @@ #include #include #include +#include #include "setup.h" @@ -331,6 +332,12 @@ void __init early_setup(unsigned long dt_ptr) */ configure_exceptions(); + /* + * Configure Kernel Userspace Protection. This needs to happen before + * feature fixups for platforms that implement this using features. + */ + setup_kup(); + /* Apply all the dynamic patching */ apply_feature_fixups(); setup_feature_keys(); diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c index 2b656e67f2ea..a72bbfc3add6 100644 --- a/arch/powerpc/mm/init-common.c +++ b/arch/powerpc/mm/init-common.c @@ -24,6 +24,11 @@ #include #include #include +#include + +void __init setup_kup(void) +{ +} static void pgd_ctor(void *addr) { diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c index 3e59e5d64b01..93cfa8cf015d 100644 --- a/arch/powerpc/mm/init_32.c +++ b/arch/powerpc/mm/init_32.c @@ -45,6 +45,7 @@ #include #include #include +#include #include "mmu_decl.h" @@ -182,6 +183,8 @@ void __init MMU_init(void) btext_unmap(); #endif + setup_kup(); + /* Shortly after that, the entire linear mapping will be available */ memblock_set_current_limit(lowmem_end_addr); }