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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 6AC5DC433DB for ; Fri, 15 Jan 2021 10:50:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4610123603 for ; Fri, 15 Jan 2021 10:50:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731996AbhAOKuc (ORCPT ); Fri, 15 Jan 2021 05:50:32 -0500 Received: from mail.kernel.org ([198.145.29.99]:37998 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726370AbhAOKub (ORCPT ); Fri, 15 Jan 2021 05:50:31 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2CCB722583; Fri, 15 Jan 2021 10:49:48 +0000 (UTC) Date: Fri, 15 Jan 2021 10:49:45 +0000 From: Catalin Marinas To: Andrey Konovalov Cc: Andrew Morton , Vincenzo Frascino , Dmitry Vyukov , Alexander Potapenko , Marco Elver , Will Deacon , Andrey Ryabinin , Peter Collingbourne , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] kasan, arm64: fix pointer tags in KASAN reports Message-ID: <20210115104945.GB16707@gaia> References: <3d9e6dece676e9da49d9913c78fd647db7dad552.1610652791.git.andreyknvl@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3d9e6dece676e9da49d9913c78fd647db7dad552.1610652791.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 Thu, Jan 14, 2021 at 08:33:57PM +0100, Andrey Konovalov wrote: > As of the "arm64: expose FAR_EL1 tag bits in siginfo" patch, the address > that is passed to report_tag_fault has pointer tags in the format of 0x0X, > while KASAN uses 0xFX format (note the difference in the top 4 bits). > > Fix up the pointer tag before calling kasan_report. > > Link: https://linux-review.googlesource.com/id/I9ced973866036d8679e8f4ae325de547eb969649 > Fixes: dceec3ff7807 ("arm64: expose FAR_EL1 tag bits in siginfo") > Fixes: 4291e9ee6189 ("kasan, arm64: print report from tag fault handler") > Signed-off-by: Andrey Konovalov > --- > arch/arm64/mm/fault.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c > index 3c40da479899..a218f6f2fdc8 100644 > --- a/arch/arm64/mm/fault.c > +++ b/arch/arm64/mm/fault.c > @@ -304,6 +304,8 @@ static void report_tag_fault(unsigned long addr, unsigned int esr, > { > bool is_write = ((esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT) != 0; > > + /* The format of KASAN tags is 0xF. */ > + addr |= (0xF0UL << MTE_TAG_SHIFT); > /* > * SAS bits aren't set for all faults reported in EL1, so we can't > * find out access size. I already replied here but I don't see any change in v2: https://lore.kernel.org/linux-arm-kernel/20210113165441.GC27045@gaia/ -- Catalin