From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f197.google.com (mail-wr0-f197.google.com [209.85.128.197]) by kanga.kvack.org (Postfix) with ESMTP id 4BD246B000C for ; Fri, 20 Apr 2018 10:47:12 -0400 (EDT) Received: by mail-wr0-f197.google.com with SMTP id l6-v6so2919129wrn.17 for ; Fri, 20 Apr 2018 07:47:12 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id h14-v6sor2801011wre.70.2018.04.20.07.47.11 for (Google Transport Security); Fri, 20 Apr 2018 07:47:11 -0700 (PDT) From: Andrey Konovalov Subject: [RFC PATCH v3 06/15] khwasan, arm64: fix up fault handling logic Date: Fri, 20 Apr 2018 16:46:44 +0200 Message-Id: <4aaaba7c1788004c1cb654787f005efbe47eca6a.1524235387.git.andreyknvl@google.com> In-Reply-To: References: In-Reply-To: References: Sender: owner-linux-mm@kvack.org List-ID: To: Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Jonathan Corbet , Catalin Marinas , Will Deacon , Marc Zyngier , Christopher Li , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Masahiro Yamada , Michal Marek , "GitAuthor : Andrey Konovalov" , Mark Rutland , Ard Biesheuvel , Yury Norov , Nick Desaulniers , Suzuki K Poulose , Kristina Martsenko , Punit Agrawal , Dave Martin , Michael Weiser , James Morse , Julien Thierry , Steve Capper , Tyler Baicar , "Eric W . Biederman" , Thomas Gleixner , Ingo Molnar , Paul Lawrence , Greg Kroah-Hartman , David Woodhouse , Sandipan Das , Kees Cook , Herbert Xu , Geert Uytterhoeven , Josh Poimboeuf , Arnd Bergmann , kasan-dev@googlegroups.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-sparse@vger.kernel.org, linux-mm@kvack.org, linux-kbuild@vger.kernel.org Cc: Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Kees Cook , Jann Horn , Mark Brand show_pte in arm64 fault handling relies on the fact that the top byte of a kernel pointer is 0xff, which isn't always the case with KHWASAN enabled. Reset the top byte. Signed-off-by: Andrey Konovalov --- arch/arm64/mm/fault.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 4165485e8b6e..e834fe76f5d2 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -134,6 +135,8 @@ void show_pte(unsigned long addr) pgd_t *pgdp; pgd_t pgd; + addr = (unsigned long)khwasan_reset_tag((void *)addr); + if (addr < TASK_SIZE) { /* TTBR0 */ mm = current->active_mm; -- 2.17.0.484.g0c8726318c-goog