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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 7B166C2D0CE for ; Mon, 30 Dec 2019 08:24:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 51A46207FF for ; Mon, 30 Dec 2019 08:24:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577694242; bh=Biwwd4LtakB9FdBdd5i14+uCUU5zhzHTcRb4d34SM+I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=GOCrf02YwxNdYQqwcQjneaETHyTHcEDdcPJO//k0LZvYGEyjgN/Qj9HSbuYeBdtYS koT8LRZb0voiP1GFWX6/g86nFjJ8dvuj/6WM4aVJH0cEBGUOddNo1Z9Bqlx09KUgfi +LnW3XBjxb9ADgm6uPrr8wgk66E2Rzpc+hoP3nRo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727243AbfL3IX7 (ORCPT ); Mon, 30 Dec 2019 03:23:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:47690 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727175AbfL3IX7 (ORCPT ); Mon, 30 Dec 2019 03:23:59 -0500 Received: from localhost.localdomain (unknown [223.93.147.148]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 00C0F207FF; Mon, 30 Dec 2019 08:23:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577694238; bh=Biwwd4LtakB9FdBdd5i14+uCUU5zhzHTcRb4d34SM+I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P7Ha0AenroDw3q4MNiJZlXZl2f7iSDn4SeashT61kvkX3BXy/sUAAxkVAJNf8q4Y7 snqFyYwhLWsS4OLzQPaYPRhMXbuDvHhEJaNlyrEp0RcZCMnFQPosDsqVEgJhW0fOpw gU8t3sZzpB5aKBwF71+BOVmU79ZHajwYyDiWIHy4= From: guoren@kernel.org To: linux-csky@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, arnd@arndb.de, Mao Han , Guo Ren Subject: [PATCH 2/5] csky: Initial stack protector support Date: Mon, 30 Dec 2019 16:23:28 +0800 Message-Id: <20191230082331.30976-2-guoren@kernel.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20191230082331.30976-1-guoren@kernel.org> References: <20191230082331.30976-1-guoren@kernel.org> Sender: linux-csky-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-csky@vger.kernel.org From: Mao Han This is a basic -fstack-protector support without per-task canary switching. The protector will report something like when stack corruption is detected: It's tested with strcpy local array overflow in sys_kill and get: stack-protector: Kernel stack is corrupted in: sys_kill+0x23c/0x23c TODO: - Support task switch for different cannary Signed-off-by: Mao Han Signed-off-by: Guo Ren --- arch/csky/Kconfig | 1 + arch/csky/include/asm/stackprotector.h | 29 ++++++++++++++++++++++++++ arch/csky/kernel/process.c | 6 ++++++ 3 files changed, 36 insertions(+) create mode 100644 arch/csky/include/asm/stackprotector.h diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig index 3973847b5f42..285234300740 100644 --- a/arch/csky/Kconfig +++ b/arch/csky/Kconfig @@ -48,6 +48,7 @@ config CSKY select HAVE_PERF_USER_STACK_DUMP select HAVE_DMA_API_DEBUG select HAVE_DMA_CONTIGUOUS + select HAVE_STACKPROTECTOR select HAVE_SYSCALL_TRACEPOINTS select MAY_HAVE_SPARSE_IRQ select MODULES_USE_ELF_RELA if MODULES diff --git a/arch/csky/include/asm/stackprotector.h b/arch/csky/include/asm/stackprotector.h new file mode 100644 index 000000000000..d7cd4e51edd9 --- /dev/null +++ b/arch/csky/include/asm/stackprotector.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_STACKPROTECTOR_H +#define _ASM_STACKPROTECTOR_H 1 + +#include +#include + +extern unsigned long __stack_chk_guard; + +/* + * Initialize the stackprotector canary value. + * + * NOTE: this must only be called from functions that never return, + * and it must always be inlined. + */ +static __always_inline void boot_init_stack_canary(void) +{ + unsigned long canary; + + /* Try to get a semi random initial value. */ + get_random_bytes(&canary, sizeof(canary)); + canary ^= LINUX_VERSION_CODE; + canary &= CANARY_MASK; + + current->stack_canary = canary; + __stack_chk_guard = current->stack_canary; +} + +#endif /* __ASM_SH_STACKPROTECTOR_H */ diff --git a/arch/csky/kernel/process.c b/arch/csky/kernel/process.c index f320d9248a22..5349cd8c0f30 100644 --- a/arch/csky/kernel/process.c +++ b/arch/csky/kernel/process.c @@ -16,6 +16,12 @@ struct cpuinfo_csky cpu_data[NR_CPUS]; +#ifdef CONFIG_STACKPROTECTOR +#include +unsigned long __stack_chk_guard __read_mostly; +EXPORT_SYMBOL(__stack_chk_guard); +#endif + asmlinkage void ret_from_fork(void); asmlinkage void ret_from_kernel_thread(void); -- 2.17.0