From patchwork Wed Feb 16 13:13:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 12748530 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 477FAC43219 for ; Wed, 16 Feb 2022 13:18:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234117AbiBPNSi (ORCPT ); Wed, 16 Feb 2022 08:18:38 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:35400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233897AbiBPNRr (ORCPT ); Wed, 16 Feb 2022 08:17:47 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A6966293B42; Wed, 16 Feb 2022 05:17:24 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 44D81616B4; Wed, 16 Feb 2022 13:17:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3BB5FC340F1; Wed, 16 Feb 2022 13:17:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645017443; bh=MxlH7OSdWg2oRBDys6vsaBDtcNFNrqae9GgCDj46MDk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sjI1N/Ysf6UohThwc+VXydeUqwNugfP8doF9H67EicATD6oaAkDsrCNS3AC/ubFNd ziBIxKGEAeyq4Bw3XdZgjBuNcKHeB1enctrHaLGU2ykGVgZHDsnbC5Wzwde0sZPsGo WD7WBQJHRS/PhCcVbk/s6TQX9q0zFJnPZsK3bgY0sTLsXoxe2RYo46AhoXLG6T8vLY ptfvBD5j0ki8uiIVLlwxNojr8S73bqQ6CnNgAESnFCyQrATHgA3qg0Clpwhp7O6ene UNjiTeS5j4av8zOGlm3gJWoU7z2Cw6gaTV6tNodGA/Zj7EYErzSRxKmSguUvyWCtWL X2GGlpG3o7PVg== From: Arnd Bergmann To: Linus Torvalds , Christoph Hellwig , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, arnd@arndb.de, linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk Cc: linux@armlinux.org.uk, will@kernel.org, guoren@kernel.org, bcain@codeaurora.org, geert@linux-m68k.org, monstr@monstr.eu, tsbogend@alpha.franken.de, nickhu@andestech.com, green.hu@gmail.com, dinguyen@kernel.org, shorne@gmail.com, deller@gmx.de, mpe@ellerman.id.au, peterz@infradead.org, mingo@redhat.com, mark.rutland@arm.com, hca@linux.ibm.com, dalias@libc.org, davem@davemloft.net, richard@nod.at, x86@kernel.org, jcmvbkbc@gmail.com, ebiederm@xmission.com, akpm@linux-foundation.org, ardb@kernel.org, linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, openrisc@lists.librecores.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, linux-xtensa@linux-xtensa.org Subject: [PATCH v2 10/18] m68k: fix access_ok for coldfire Date: Wed, 16 Feb 2022 14:13:24 +0100 Message-Id: <20220216131332.1489939-11-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20220216131332.1489939-1-arnd@kernel.org> References: <20220216131332.1489939-1-arnd@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org From: Arnd Bergmann While most m68k platforms use separate address spaces for user and kernel space, at least coldfire does not, and the other ones have a TASK_SIZE that is less than the entire 4GB address range. Using the default implementation of __access_ok() stops coldfire user space from trivially accessing kernel memory. Signed-off-by: Arnd Bergmann Reviewed-by: Christoph Hellwig --- arch/m68k/include/asm/uaccess.h | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/m68k/include/asm/uaccess.h b/arch/m68k/include/asm/uaccess.h index 79617c0b2f91..8eb625e75452 100644 --- a/arch/m68k/include/asm/uaccess.h +++ b/arch/m68k/include/asm/uaccess.h @@ -12,14 +12,21 @@ #include /* We let the MMU do all checking */ -static inline int access_ok(const void __user *addr, +static inline int access_ok(const void __user *ptr, unsigned long size) { + unsigned long limit = TASK_SIZE; + unsigned long addr = (unsigned long)ptr; + /* * XXX: for !CONFIG_CPU_HAS_ADDRESS_SPACES this really needs to check * for TASK_SIZE! + * Removing this helper is probably sufficient. */ - return 1; + if (IS_ENABLED(CONFIG_CPU_HAS_ADDRESS_SPACES)) + return 1; + + return (size <= limit) && (addr <= (limit - size)); } /*