From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753097AbcAGS4z (ORCPT ); Thu, 7 Jan 2016 13:56:55 -0500 Received: from mail-pa0-f48.google.com ([209.85.220.48]:35201 "EHLO mail-pa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752081AbcAGS4y (ORCPT ); Thu, 7 Jan 2016 13:56:54 -0500 Date: Thu, 7 Jan 2016 10:56:51 -0800 From: Kees Cook To: Russell King Cc: Arnd Bergmann , Simon Horman , Geert Uytterhoeven , Laurent Pinchart , Magnus Damm , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v4] ARM: fix atags_to_fdt with stack-protector-strong Message-ID: <20160107185651.GA4928@www.outflux.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Building with CONFIG_CC_STACKPROTECTOR_STRONG triggers protection code generation under CONFIG_ARM_ATAG_DTB_COMPAT but this is too early for being able to use any of the stack_chk code. Explicitly disable it for only the atags_to_fdt bits. Suggested-by: zhxihu Signed-off-by: Kees Cook Acked-by: Arnd Bergmann --- v4: - single invocation of cc-option, rmk - kept arnd's ack, since it's functionally the same as v3 v3: - actually send to everyone correctly v2: - use call cc-option unconditionally, arnd --- arch/arm/boot/compressed/Makefile | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 3f9a9ebc77c3..f0a75d9e1648 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -106,6 +106,15 @@ ORIG_CFLAGS := $(KBUILD_CFLAGS) KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS)) endif +# -fstack-protector-strong triggers protection checks in this code, +# but it is being used too early to link to meaningful stack_chk logic. +nossp_flags := $(call cc-option, -fno-stack-protector) +CFLAGS_atags_to_fdt.o := $(nossp_flags) +CFLAGS_fdt.o := $(nossp_flags) +CFLAGS_fdt_ro.o := $(nossp_flags) +CFLAGS_fdt_rw.o := $(nossp_flags) +CFLAGS_fdt_wip.o := $(nossp_flags) + ccflags-y := -fpic -mno-single-pic-base -fno-builtin -I$(obj) asflags-y := -DZIMAGE -- 2.6.3 -- Kees Cook Chrome OS & Brillo Security