From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id 1DC186B0261 for ; Thu, 30 Nov 2017 11:33:29 -0500 (EST) Received: by mail-pf0-f199.google.com with SMTP id r88so5196952pfi.23 for ; Thu, 30 Nov 2017 08:33:29 -0800 (PST) Received: from EUR03-DB5-obe.outbound.protection.outlook.com (mail-eopbgr40112.outbound.protection.outlook.com. [40.107.4.112]) by mx.google.com with ESMTPS id s78si3507991pfj.225.2017.11.30.08.33.27 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 30 Nov 2017 08:33:27 -0800 (PST) Subject: Re: [PATCH v2 4/5] kasan: support LLVM-style asan parameters References: <20171129215050.158653-1-paullawrence@google.com> <20171129215050.158653-5-paullawrence@google.com> From: Andrey Ryabinin Message-ID: <7e9f3194-17c1-9dc5-9392-748801c831bd@virtuozzo.com> Date: Thu, 30 Nov 2017 19:36:54 +0300 MIME-Version: 1.0 In-Reply-To: <20171129215050.158653-5-paullawrence@google.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Paul Lawrence , Alexander Potapenko , Dmitry Vyukov , Masahiro Yamada , Michal Marek Cc: linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kbuild@vger.kernel.org, Matthias Kaehlcke , Michael Davidson , Greg Hackmann On 11/30/2017 12:50 AM, Paul Lawrence wrote: > Use cc-option to figure out whether the compiler's sanitizer uses > LLVM-style parameters ("-mllvm -asan-foo=bar") or GCC-style parameters > ("--param asan-foo=bar"). > > Signed-off-by: Greg Hackmann > Signed-off-by: Paul Lawrence > > --- > scripts/Makefile.kasan | 39 +++++++++++++++++++++++++++------------ > 1 file changed, 27 insertions(+), 12 deletions(-) > It looks rather messy. Try the following patch. Note, that I didn't add asan-instrument-allocas=1 because it has nothing to do with LLVM-style params support. asan-instrument-allocas should probably be in the patch that adds alloca() support. From: Andrey Ryabinin Subject: [PATCH] kasan/Makefile: Support LLVM style asan parameters. LLVM doesn't understand GCC-style paramters ("--param asan-foo=bar"), thus we currently we don't use inline/globals/stack instrumentation when building the kernel with clang. Add support for LLVM-style parameters ("-mllvm -asan-foo=bar") to enable all KASAN features. Signed-off-by: Andrey Ryabinin --- scripts/Makefile.kasan | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-) diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan index 1ce7115aa499..2af5977c394d 100644 --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -10,10 +10,7 @@ KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET) CFLAGS_KASAN_MINIMAL := -fsanitize=kernel-address -CFLAGS_KASAN := $(call cc-option, -fsanitize=kernel-address \ - -fasan-shadow-offset=$(KASAN_SHADOW_OFFSET) \ - --param asan-stack=1 --param asan-globals=1 \ - --param asan-instrumentation-with-call-threshold=$(call_threshold)) +cc-param = $(call cc-option, --param $(1)) $(call cc-option, -mllvm -$(1)) ifeq ($(call cc-option, $(CFLAGS_KASAN_MINIMAL) -Werror),) ifneq ($(CONFIG_COMPILE_TEST),y) @@ -21,13 +18,23 @@ ifeq ($(call cc-option, $(CFLAGS_KASAN_MINIMAL) -Werror),) -fsanitize=kernel-address is not supported by compiler) endif else - ifeq ($(CFLAGS_KASAN),) - ifneq ($(CONFIG_COMPILE_TEST),y) - $(warning CONFIG_KASAN: compiler does not support all options.\ - Trying minimal configuration) - endif - CFLAGS_KASAN := $(CFLAGS_KASAN_MINIMAL) - endif + # -fasan-shadow-offset fails without -fsanitize + CFLAGS_KASAN_SHADOW := $(call cc-option, -fsanitize=kernel-address \ + -fasan-shadow-offset=$(KASAN_SHADOW_OFFSET), \ + $(call cc-option, -fsanitize=kernel-address \ + -mllvm -asan-mapping-offset=$(KASAN_SHADOW_OFFSET))) + + ifeq ($(CFLAGS_KASAN_SHADOW),) + CFLAGS_KASAN := $(CFLAGS_KASAN_MINIMAL) + else + # Now add all the compiler specific options that are valid standalone + CFLAGS_KASAN := $(CFLAGS_KASAN_SHADOW) \ + $(call cc-param,asan-globals=1) \ + $(call cc-param,asan-instrumentation-with-call-threshold=$(call_threshold)) \ + $(call cc-param,asan-stack=1) \ + $(call cc-param,asan-use-after-scope=1) + endif + endif CFLAGS_KASAN += $(call cc-option, -fsanitize-address-use-after-scope) -- 2.13.6 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org