From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758749AbcILMiF (ORCPT ); Mon, 12 Sep 2016 08:38:05 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:46631 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1758705AbcILMh7 (ORCPT ); Mon, 12 Sep 2016 08:37:59 -0400 X-IBM-Helo: d06dlp02.portsmouth.uk.ibm.com X-IBM-MailFrom: borntraeger@de.ibm.com X-IBM-RcptTo: linux-kbuild@vger.kernel.org;linux-kernel@vger.kernel.org;linux-s390@vger.kernel.org From: Christian Borntraeger To: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org Cc: Heiko Carstens , Martin Schwidefsky , Michal Marek , Andrey Ryabinin , Yang Shi , Andrew Morton , Christian Borntraeger Subject: [PATCH 1/2] ubsan: allow to disable the null sanitizer Date: Mon, 12 Sep 2016 14:37:19 +0200 X-Mailer: git-send-email 2.5.5 In-Reply-To: <1473683840-8700-1-git-send-email-borntraeger@de.ibm.com> References: <1473683840-8700-1-git-send-email-borntraeger@de.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16091212-0032-0000-0000-0000020BE909 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16091212-0033-0000-0000-00001CCC1773 Message-Id: <1473683840-8700-2-git-send-email-borntraeger@de.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-09-12_06:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1609020000 definitions=main-1609120195 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some architectures use a hardware defined struct at address zero. Checking for a null pointer will result in many ubsan reports. Let users disable the null sanitizer. Signed-off-by: Christian Borntraeger --- lib/Kconfig.ubsan | 11 +++++++++++ scripts/Makefile.ubsan | 5 ++++- 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan index 39494af..851c3f2 100644 --- a/lib/Kconfig.ubsan +++ b/lib/Kconfig.ubsan @@ -1,6 +1,9 @@ config ARCH_HAS_UBSAN_SANITIZE_ALL bool +config ARCH_WANTS_UBSAN_NO_NULL + def_bool n + config UBSAN bool "Undefined behaviour sanity checker" help @@ -34,3 +37,11 @@ config UBSAN_ALIGNMENT This option enables detection of unaligned memory accesses. Enabling this option on architectures that support unaligned accesses may produce a lot of false positives. + +config UBSAN_NULL + bool "Enable checking of null pointers" + depends on UBSAN + default y if UBSAN && !ARCH_WANTS_UBSAN_NO_NULL + help + This option enables detection of memory accesses via a + null pointer. diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan index 77ce538..3b1b138 100644 --- a/scripts/Makefile.ubsan +++ b/scripts/Makefile.ubsan @@ -3,7 +3,6 @@ ifdef CONFIG_UBSAN CFLAGS_UBSAN += $(call cc-option, -fsanitize=integer-divide-by-zero) CFLAGS_UBSAN += $(call cc-option, -fsanitize=unreachable) CFLAGS_UBSAN += $(call cc-option, -fsanitize=vla-bound) - CFLAGS_UBSAN += $(call cc-option, -fsanitize=null) CFLAGS_UBSAN += $(call cc-option, -fsanitize=signed-integer-overflow) CFLAGS_UBSAN += $(call cc-option, -fsanitize=bounds) CFLAGS_UBSAN += $(call cc-option, -fsanitize=object-size) @@ -15,6 +14,10 @@ ifdef CONFIG_UBSAN_ALIGNMENT CFLAGS_UBSAN += $(call cc-option, -fsanitize=alignment) endif +ifdef CONFIG_UBSAN_NULL + CFLAGS_UBSAN += $(call cc-option, -fsanitize=null) +endif + # -fsanitize=* options makes GCC less smart than usual and # increase number of 'maybe-uninitialized false-positives CFLAGS_UBSAN += $(call cc-option, -Wno-maybe-uninitialized) -- 2.5.5