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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 B0A21C48BD3 for ; Wed, 26 Jun 2019 16:17:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D3A5217D7 for ; Wed, 26 Jun 2019 16:17:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726480AbfFZQRx (ORCPT ); Wed, 26 Jun 2019 12:17:53 -0400 Received: from foss.arm.com ([217.140.110.172]:36476 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726341AbfFZQRx (ORCPT ); Wed, 26 Jun 2019 12:17:53 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 458BE2B; Wed, 26 Jun 2019 09:17:52 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 93CED3F706; Wed, 26 Jun 2019 09:17:50 -0700 (PDT) Date: Wed, 26 Jun 2019 17:17:48 +0100 From: Mark Rutland To: Marco Elver Cc: linux-kernel@vger.kernel.org, Andrey Ryabinin , Dmitry Vyukov , Alexander Potapenko , Andrey Konovalov , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , kasan-dev@googlegroups.com, linux-mm@kvack.org Subject: Re: [PATCH v3 1/5] mm/kasan: Introduce __kasan_check_{read,write} Message-ID: <20190626161748.GH20635@lakrids.cambridge.arm.com> References: <20190626142014.141844-1-elver@google.com> <20190626142014.141844-2-elver@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190626142014.141844-2-elver@google.com> User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 26, 2019 at 04:20:10PM +0200, Marco Elver wrote: > This introduces __kasan_check_{read,write}. __kasan_check functions may > be used from anywhere, even compilation units that disable > instrumentation selectively. > > This change eliminates the need for the __KASAN_INTERNAL definition. > > Signed-off-by: Marco Elver > Cc: Andrey Ryabinin > Cc: Dmitry Vyukov > Cc: Alexander Potapenko > Cc: Andrey Konovalov > Cc: Christoph Lameter > Cc: Pekka Enberg > Cc: David Rientjes > Cc: Joonsoo Kim > Cc: Andrew Morton > Cc: Mark Rutland > Cc: kasan-dev@googlegroups.com > Cc: linux-kernel@vger.kernel.org > Cc: linux-mm@kvack.org Logically this makes sense to me, so FWIW: Acked-by: Mark Rutland Thanks, Mark. > --- > v3: > * Fix Formatting and split introduction of __kasan_check_* and returning > bool into 2 patches. > --- > include/linux/kasan-checks.h | 31 ++++++++++++++++++++++++++++--- > mm/kasan/common.c | 10 ++++------ > 2 files changed, 32 insertions(+), 9 deletions(-) > > diff --git a/include/linux/kasan-checks.h b/include/linux/kasan-checks.h > index a61dc075e2ce..19a0175d2452 100644 > --- a/include/linux/kasan-checks.h > +++ b/include/linux/kasan-checks.h > @@ -2,9 +2,34 @@ > #ifndef _LINUX_KASAN_CHECKS_H > #define _LINUX_KASAN_CHECKS_H > > -#if defined(__SANITIZE_ADDRESS__) || defined(__KASAN_INTERNAL) > -void kasan_check_read(const volatile void *p, unsigned int size); > -void kasan_check_write(const volatile void *p, unsigned int size); > +/* > + * __kasan_check_*: Always available when KASAN is enabled. This may be used > + * even in compilation units that selectively disable KASAN, but must use KASAN > + * to validate access to an address. Never use these in header files! > + */ > +#ifdef CONFIG_KASAN > +void __kasan_check_read(const volatile void *p, unsigned int size); > +void __kasan_check_write(const volatile void *p, unsigned int size); > +#else > +static inline void __kasan_check_read(const volatile void *p, unsigned int size) > +{ } > +static inline void __kasan_check_write(const volatile void *p, unsigned int size) > +{ } > +#endif > + > +/* > + * kasan_check_*: Only available when the particular compilation unit has KASAN > + * instrumentation enabled. May be used in header files. > + */ > +#ifdef __SANITIZE_ADDRESS__ > +static inline void kasan_check_read(const volatile void *p, unsigned int size) > +{ > + __kasan_check_read(p, size); > +} > +static inline void kasan_check_write(const volatile void *p, unsigned int size) > +{ > + __kasan_check_read(p, size); > +} > #else > static inline void kasan_check_read(const volatile void *p, unsigned int size) > { } > diff --git a/mm/kasan/common.c b/mm/kasan/common.c > index 242fdc01aaa9..6bada42cc152 100644 > --- a/mm/kasan/common.c > +++ b/mm/kasan/common.c > @@ -14,8 +14,6 @@ > * > */ > > -#define __KASAN_INTERNAL > - > #include > #include > #include > @@ -89,17 +87,17 @@ void kasan_disable_current(void) > current->kasan_depth--; > } > > -void kasan_check_read(const volatile void *p, unsigned int size) > +void __kasan_check_read(const volatile void *p, unsigned int size) > { > check_memory_region((unsigned long)p, size, false, _RET_IP_); > } > -EXPORT_SYMBOL(kasan_check_read); > +EXPORT_SYMBOL(__kasan_check_read); > > -void kasan_check_write(const volatile void *p, unsigned int size) > +void __kasan_check_write(const volatile void *p, unsigned int size) > { > check_memory_region((unsigned long)p, size, true, _RET_IP_); > } > -EXPORT_SYMBOL(kasan_check_write); > +EXPORT_SYMBOL(__kasan_check_write); > > #undef memset > void *memset(void *addr, int c, size_t len) > -- > 2.22.0.410.gd8fdbe21b5-goog >