From patchwork Tue Mar 12 22:16:19 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe Leroy X-Patchwork-Id: 10850075 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6E3F31575 for ; Tue, 12 Mar 2019 22:16:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5A9ED286BC for ; Tue, 12 Mar 2019 22:16:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4F13B296F7; Tue, 12 Mar 2019 22:16:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C5F1B286BC for ; Tue, 12 Mar 2019 22:16:51 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6D74A8E000E; Tue, 12 Mar 2019 18:16:23 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 6402C8E0011; Tue, 12 Mar 2019 18:16:23 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 445D18E000E; Tue, 12 Mar 2019 18:16:23 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by kanga.kvack.org (Postfix) with ESMTP id D730D8E0011 for ; Tue, 12 Mar 2019 18:16:22 -0400 (EDT) Received: by mail-wm1-f69.google.com with SMTP id n12so1032387wmc.2 for ; Tue, 12 Mar 2019 15:16:22 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:message-id:in-reply-to:references :from:subject:to:cc:date; bh=3EkWwfm1J9eIRyBAvVT+4ioqJyrfykTcLJkz42zJae0=; b=H4nSBunyH0WGcWb9WOMAm9XGHn4m3NQm96dNU9rVyK4uo9TrmJZVbbZ/8ZdCViaOae FSH7fn9Z+asO2XaBavF1AfVAECj9LwLNuaCYui/3JtIMAStKjEhrsPWxXLb5+q23nzUw WJ8UzjAi/IcYEgNcBSf81KyLxhHCR9f+psJHYBg78oMHJ76zn0X0GVkLXh5PccVrxWPA yTDZ+BkEE1fDSb/FDRYxdWgT11Q4VIOcuYWDl8M5f+1bD3dlvRPyceGHBnVe/1QLE5UF L0dMXXGSWjn1AO4CylaAo29tcCqQwdTj+LQtBDylkYuaue6C+7dESUhYjG2hmUZPpl75 LlTw== X-Gm-Message-State: APjAAAVU1OTy7e6WLHNmnND+juOdq/c5F12SY7nVJ/rvXn3oknZuFKTd yh9jQ7oraOuRuTq2gOUawhBxyeAZx0kXE9AB1bwCLYkOt/zg4ur0I2L+uqm4WcRyu9wbKPX6v74 9lXEXuDMV9Tt+tdmYoMugiwubZHpTeBSkDGsq6GIVTHGRp47NLR5vUai9xetfr8NR+A== X-Received: by 2002:adf:b211:: with SMTP id u17mr27005522wra.322.1552428982289; Tue, 12 Mar 2019 15:16:22 -0700 (PDT) X-Google-Smtp-Source: APXvYqz7G3kYMpt2jBJyd0UWYJcD53hOh6m94BUFBCQiMyZ14Ignb+cVJ8VGRuSggX/axUu5AIvw X-Received: by 2002:adf:b211:: with SMTP id u17mr27005482wra.322.1552428981031; Tue, 12 Mar 2019 15:16:21 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1552428981; cv=none; d=google.com; s=arc-20160816; b=eLYREyTKUYEVXKCN0N+yXBO58XocxVMeB1GSBsA+eHBZeQRL6beC4oStI3TOQby1mu 8Cps9VCWWoNWk5r72jZ82NkutECW9+chzpqFCVgRmr+2sivTuCJEwlmcSHAqzqSCzIix fNuk7NVB15kitTMh44TiIiDCssoxaKttPpo7gFY09hgmNNdTvkT4QaRKiRVkgUGuDJ/o XpzXqlmV80daMzTQWsAPHUz0pIbgqjJkSr8yD2+fnlzXsBlF9UaQDRy/DGjUIHq0nC0R C3qorY34dcqQqmsLN1SmSYCf6Pa0D/wsC2c6Eg2UKCtstRWonB/D8lBktLt52FTBVmND kQ7Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=date:cc:to:subject:from:references:in-reply-to:message-id :dkim-signature; bh=3EkWwfm1J9eIRyBAvVT+4ioqJyrfykTcLJkz42zJae0=; b=gkk58grF3zegHLLJDZ2Pq044vVhRAphB/qP1rLqbSiKQiF7XEarzS6c1EEuRjwp5Ol +aPi8IZPQsaFyMBnpQVklXGROchFA+oN9NnI7EBlLxzosW0CtfZ9DW3DwCXzNcPjjmmS 8Mx3ui6ZZXnyh+BxnU3xWqIBIdZXuUUahtc0GQCpFPnjtkZ3ia0WHahkvqslf26EmEci 7aSmX3W/26b9WhgHKENNHi7rQ6ouwtVxxMp11DMcQZ06uUBInCU147TNrjV/ZmC//aQo ZjTXrGOnpoaRDd3FaVpxkVc35QcxuWKWYRPTndIfUrMfrflgWOLcSfFkZ6a0M06jVyOQ vFpA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@c-s.fr header.s=mail header.b=N2TM9CNF; spf=pass (google.com: domain of christophe.leroy@c-s.fr designates 93.17.236.30 as permitted sender) smtp.mailfrom=christophe.leroy@c-s.fr Received: from pegase1.c-s.fr (pegase1.c-s.fr. [93.17.236.30]) by mx.google.com with ESMTPS id x10si18308wmj.95.2019.03.12.15.16.20 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 12 Mar 2019 15:16:21 -0700 (PDT) Received-SPF: pass (google.com: domain of christophe.leroy@c-s.fr designates 93.17.236.30 as permitted sender) client-ip=93.17.236.30; Authentication-Results: mx.google.com; dkim=pass header.i=@c-s.fr header.s=mail header.b=N2TM9CNF; spf=pass (google.com: domain of christophe.leroy@c-s.fr designates 93.17.236.30 as permitted sender) smtp.mailfrom=christophe.leroy@c-s.fr Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 44Jq7S2kbMz9tyln; Tue, 12 Mar 2019 23:16:20 +0100 (CET) Authentication-Results: localhost; dkim=pass reason="1024-bit key; insecure key" header.d=c-s.fr header.i=@c-s.fr header.b=N2TM9CNF; dkim-adsp=pass; dkim-atps=neutral X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id qTzJ1ppy2_Hj; Tue, 12 Mar 2019 23:16:20 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 44Jq7S1Z5Wz9tyll; Tue, 12 Mar 2019 23:16:20 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=c-s.fr; s=mail; t=1552428980; bh=3EkWwfm1J9eIRyBAvVT+4ioqJyrfykTcLJkz42zJae0=; h=In-Reply-To:References:From:Subject:To:Cc:Date:From; b=N2TM9CNFJJZcGDGQgUrPK4MYpe/al6eQHIrgQrWJWcmO2YuKobOm5OK7m9EZlK0xG B6uP41oS5KK5Jzh2rvnrRFvwrgHFS7B2fPk83j6E4FGdrrsJp5+yXVRo5lW+ecBbLf qaXPTXztGHCEFMxvL91DA/r2eFRyTqWevkyabkZU= Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 6F1D48B8B1; Tue, 12 Mar 2019 23:16:20 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id Q5Qbh1RmwQXX; Tue, 12 Mar 2019 23:16:20 +0100 (CET) Received: from po16846vm.idsi0.si.c-s.fr (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 46EAC8B8A7; Tue, 12 Mar 2019 23:16:20 +0100 (CET) Received: by po16846vm.idsi0.si.c-s.fr (Postfix, from userid 0) id 0AB216FA15; Tue, 12 Mar 2019 22:16:19 +0000 (UTC) Message-Id: <053c7aa774fe73402e690c47f432c9d3279dfc30.1552428161.git.christophe.leroy@c-s.fr> In-Reply-To: References: From: Christophe Leroy Subject: [PATCH v10 14/18] powerpc/32s: map kasan zero shadow with PAGE_READONLY instead of PAGE_KERNEL_RO To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Nicholas Piggin , Aneesh Kumar K.V , Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Daniel Axtens Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kasan-dev@googlegroups.com, linux-mm@kvack.org Date: Tue, 12 Mar 2019 22:16:19 +0000 (UTC) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP For hash32, the zero shadow page gets mapped with PAGE_READONLY instead of PAGE_KERNEL_RO, because the PP bits don't provide a RO kernel, so PAGE_KERNEL_RO is equivalent to PAGE_KERNEL. By using PAGE_READONLY, the page is RO for both kernel and user, but this is not a security issue as it contains only zeroes. Signed-off-by: Christophe Leroy --- arch/powerpc/mm/kasan/kasan_init_32.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c index ba8361487075..0d62be3cba47 100644 --- a/arch/powerpc/mm/kasan/kasan_init_32.c +++ b/arch/powerpc/mm/kasan/kasan_init_32.c @@ -39,7 +39,10 @@ static int kasan_init_shadow_page_tables(unsigned long k_start, unsigned long k_ if (!new) return -ENOMEM; - kasan_populate_pte(new, PAGE_KERNEL_RO); + if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE)) + kasan_populate_pte(new, PAGE_READONLY); + else + kasan_populate_pte(new, PAGE_KERNEL_RO); pmd_populate_kernel(&init_mm, pmd, new); } return 0; @@ -84,7 +87,10 @@ static int __ref kasan_init_region(void *start, size_t size) static void __init kasan_remap_early_shadow_ro(void) { - kasan_populate_pte(kasan_early_shadow_pte, PAGE_KERNEL_RO); + if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE)) + kasan_populate_pte(kasan_early_shadow_pte, PAGE_READONLY); + else + kasan_populate_pte(kasan_early_shadow_pte, PAGE_KERNEL_RO); flush_tlb_kernel_range(KASAN_SHADOW_START, KASAN_SHADOW_END); }