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=-8.6 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,URIBL_BLOCKED,USER_AGENT_SANE_1 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 1F83DC2D0DB for ; Wed, 29 Jan 2020 19:13:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C461C207FD for ; Wed, 29 Jan 2020 19:13:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580325229; bh=92ff4QxUOJxWhCCK6LSimpjMkzXTi+lzOK+GW8Ovhh8=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:List-ID: From; b=P+/WiHVprKP51KAPkfl5AybCwj3qYCFkAgFO5osT5h68lsW6AOLVVfvImwtFZmXWo n5B+SWggz0xs9gBfF9YNEHqGI9jFSdKsDY2+0l1CHzy3GpK1mvSQzgdug/CoKDoMEZ VZDpoaOwHDtHiYRsqIBRF/5KrWcGxIvJqgKd/d+Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727213AbgA2TNt (ORCPT ); Wed, 29 Jan 2020 14:13:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:33754 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726183AbgA2TNs (ORCPT ); Wed, 29 Jan 2020 14:13:48 -0500 Received: from paulmck-ThinkPad-P72.home (unknown [199.201.64.141]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C476B205F4; Wed, 29 Jan 2020 19:13:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580325227; bh=92ff4QxUOJxWhCCK6LSimpjMkzXTi+lzOK+GW8Ovhh8=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=0zQWbA7VpvkVjjcsooqJF/p4CoSQfkGAT8SsS1x9SUtpQJses139aJ6Q6F9W4Se0W y3CsJMxfjtFbiVognmRpXHnJ3QN6m9lLtApZnbI/4Fj2ko8q8GVZpJ/HJJtOXQwMai bXHRejPpx48jD36ovimq2JBngR/lM5Lvh34EfSaU= Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id 668C53521AEF; Wed, 29 Jan 2020 11:13:47 -0800 (PST) Date: Wed, 29 Jan 2020 11:13:47 -0800 From: "Paul E. McKenney" To: Dmitry Vyukov Cc: Marco Elver , Andrey Konovalov , Alexander Potapenko , kasan-dev , LKML , Mark Rutland , Will Deacon , Peter Zijlstra , Boqun Feng , Arnd Bergmann , Al Viro , Daniel Axtens , Christophe Leroy , Michael Ellerman , Masami Hiramatsu , Steven Rostedt , Ingo Molnar , Christian Brauner , Daniel Borkmann , Kees Cook , cyphar@cyphar.com, linux-arch Subject: Re: [PATCH v2 1/5] include/linux: Add instrumented.h infrastructure Message-ID: <20200129191347.GA21972@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20200121160512.70887-1-elver@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 24, 2020 at 12:22:56PM +0100, Dmitry Vyukov wrote: > On Tue, Jan 21, 2020 at 5:05 PM 'Marco Elver' via kasan-dev > wrote: > > > > This adds instrumented.h, which provides generic wrappers for memory > > access instrumentation that the compiler cannot emit for various > > sanitizers. Currently this unifies KASAN and KCSAN instrumentation. In > > future this will also include KMSAN instrumentation. > > > > Note that, copy_{to,from}_user should use special instrumentation, since > > we should be able to instrument both source and destination memory > > accesses if both are kernel memory. > > > > The current patch only instruments the memory access where the address > > is always in kernel space, however, both may in fact be kernel addresses > > when a compat syscall passes an argument allocated in the kernel to a > > real syscall. In a future change, both KASAN and KCSAN should check both > > addresses in such cases, as well as KMSAN will make use of both > > addresses. [It made more sense to provide the completed function > > signature, rather than updating it and changing all locations again at a > > later time.] > > Reviewed-by: Dmitry Vyukov I have applied this and the other four with Dmitry's Reviewed-by. Thank you all! Thanx, Paul > > Suggested-by: Arnd Bergmann > > Signed-off-by: Marco Elver > > Acked-by: Alexander Potapenko > > --- > > v2: > > * Simplify header, since we currently do not need pre/post user-copy > > distinction. > > * Make instrument_copy_{to,from}_user function arguments match > > copy_{to,from}_user and update rationale in commit message. > > --- > > include/linux/instrumented.h | 109 +++++++++++++++++++++++++++++++++++ > > 1 file changed, 109 insertions(+) > > create mode 100644 include/linux/instrumented.h > > > > diff --git a/include/linux/instrumented.h b/include/linux/instrumented.h > > new file mode 100644 > > index 000000000000..43e6ea591975 > > --- /dev/null > > +++ b/include/linux/instrumented.h > > @@ -0,0 +1,109 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > + > > +/* > > + * This header provides generic wrappers for memory access instrumentation that > > + * the compiler cannot emit for: KASAN, KCSAN. > > + */ > > +#ifndef _LINUX_INSTRUMENTED_H > > +#define _LINUX_INSTRUMENTED_H > > + > > +#include > > +#include > > +#include > > +#include > > + > > +/** > > + * instrument_read - instrument regular read access > > + * > > + * Instrument a regular read access. The instrumentation should be inserted > > + * before the actual read happens. > > + * > > + * @ptr address of access > > + * @size size of access > > + */ > > +static __always_inline void instrument_read(const volatile void *v, size_t size) > > +{ > > + kasan_check_read(v, size); > > + kcsan_check_read(v, size); > > +} > > + > > +/** > > + * instrument_write - instrument regular write access > > + * > > + * Instrument a regular write access. The instrumentation should be inserted > > + * before the actual write happens. > > + * > > + * @ptr address of access > > + * @size size of access > > + */ > > +static __always_inline void instrument_write(const volatile void *v, size_t size) > > +{ > > + kasan_check_write(v, size); > > + kcsan_check_write(v, size); > > +} > > + > > +/** > > + * instrument_atomic_read - instrument atomic read access > > + * > > + * Instrument an atomic read access. The instrumentation should be inserted > > + * before the actual read happens. > > + * > > + * @ptr address of access > > + * @size size of access > > + */ > > +static __always_inline void instrument_atomic_read(const volatile void *v, size_t size) > > +{ > > + kasan_check_read(v, size); > > + kcsan_check_atomic_read(v, size); > > +} > > + > > +/** > > + * instrument_atomic_write - instrument atomic write access > > + * > > + * Instrument an atomic write access. The instrumentation should be inserted > > + * before the actual write happens. > > + * > > + * @ptr address of access > > + * @size size of access > > + */ > > +static __always_inline void instrument_atomic_write(const volatile void *v, size_t size) > > +{ > > + kasan_check_write(v, size); > > + kcsan_check_atomic_write(v, size); > > +} > > + > > +/** > > + * instrument_copy_to_user - instrument reads of copy_to_user > > + * > > + * Instrument reads from kernel memory, that are due to copy_to_user (and > > + * variants). The instrumentation must be inserted before the accesses. > > + * > > + * @to destination address > > + * @from source address > > + * @n number of bytes to copy > > + */ > > +static __always_inline void > > +instrument_copy_to_user(void __user *to, const void *from, unsigned long n) > > +{ > > + kasan_check_read(from, n); > > + kcsan_check_read(from, n); > > +} > > + > > +/** > > + * instrument_copy_from_user - instrument writes of copy_from_user > > + * > > + * Instrument writes to kernel memory, that are due to copy_from_user (and > > + * variants). The instrumentation should be inserted before the accesses. > > + * > > + * @to destination address > > + * @from source address > > + * @n number of bytes to copy > > + */ > > +static __always_inline void > > +instrument_copy_from_user(const void *to, const void __user *from, unsigned long n) > > +{ > > + kasan_check_write(to, n); > > + kcsan_check_write(to, n); > > +} > > + > > +#endif /* _LINUX_INSTRUMENTED_H */ > > -- > > 2.25.0.341.g760bfbb309-goog > > > > -- > > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@googlegroups.com. > > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20200121160512.70887-1-elver%40google.com.