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=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,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 9DE41C2D0A3 for ; Thu, 12 Nov 2020 09:51:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 436C9205CA for ; Thu, 12 Nov 2020 09:51:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727731AbgKLJvl (ORCPT ); Thu, 12 Nov 2020 04:51:41 -0500 Received: from mail.kernel.org ([198.145.29.99]:42106 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726028AbgKLJvk (ORCPT ); Thu, 12 Nov 2020 04:51:40 -0500 Received: from gaia (unknown [2.26.170.190]) (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 95C632053B; Thu, 12 Nov 2020 09:51:37 +0000 (UTC) Date: Thu, 12 Nov 2020 09:51:35 +0000 From: Catalin Marinas To: Andrey Konovalov Cc: Dmitry Vyukov , Alexander Potapenko , Marco Elver , Will Deacon , Vincenzo Frascino , Evgenii Stepanov , Andrey Ryabinin , Branislav Rankov , Kevin Brodsky , Andrew Morton , kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 04/20] kasan, arm64: unpoison stack only with CONFIG_KASAN_STACK Message-ID: <20201112095134.GI29613@gaia> References: <7e95d4739f5617b2c1acf52f37e01f1ca83750b5.1605046662.git.andreyknvl@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7e95d4739f5617b2c1acf52f37e01f1ca83750b5.1605046662.git.andreyknvl@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 10, 2020 at 11:20:08PM +0100, Andrey Konovalov wrote: > There's a config option CONFIG_KASAN_STACK that has to be enabled for > KASAN to use stack instrumentation and perform validity checks for > stack variables. > > There's no need to unpoison stack when CONFIG_KASAN_STACK is not enabled. > Only call kasan_unpoison_task_stack[_below]() when CONFIG_KASAN_STACK is > enabled. > > Note, that CONFIG_KASAN_STACK is an option that is currently always > defined when CONFIG_KASAN is enabled, and therefore has to be tested > with #if instead of #ifdef. > > Signed-off-by: Andrey Konovalov > Link: https://linux-review.googlesource.com/id/If8a891e9fe01ea543e00b576852685afec0887e3 > --- > arch/arm64/kernel/sleep.S | 2 +- > arch/x86/kernel/acpi/wakeup_64.S | 2 +- > include/linux/kasan.h | 10 ++++++---- > mm/kasan/common.c | 2 ++ > 4 files changed, 10 insertions(+), 6 deletions(-) > > diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S > index ba40d57757d6..bdadfa56b40e 100644 > --- a/arch/arm64/kernel/sleep.S > +++ b/arch/arm64/kernel/sleep.S > @@ -133,7 +133,7 @@ SYM_FUNC_START(_cpu_resume) > */ > bl cpu_do_resume > > -#ifdef CONFIG_KASAN > +#if defined(CONFIG_KASAN) && CONFIG_KASAN_STACK > mov x0, sp > bl kasan_unpoison_task_stack_below > #endif I don't understand why CONFIG_KASAN_STACK is not a bool (do you plan to add more values to it?) but for arm64: Acked-by: Catalin Marinas