From patchwork Tue Oct 2 13:12:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10623661 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 838BF14BD for ; Tue, 2 Oct 2018 13:17:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7926C2846C for ; Tue, 2 Oct 2018 13:17:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6C08928738; Tue, 2 Oct 2018 13:17:17 +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=-2.9 required=2.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CEAAF2846C for ; Tue, 2 Oct 2018 13:17:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=6Sg2I+8QlYzpPgV/c4/TkrYVyZkIHuT4TQmW+I6dVBI=; b=UlaDb4VJu4SjEH TiOEPB96BSJLDjsELYiF+opZL8kWLdjlIEA8lZqWf9BX9rSN+MnRkVwIk7VcOY+bqv+kLxEVOe4+o P9qzeR/Uq4R+DXm7Bkyyu6ijunZbe4hVshCJRVBeqSsF6wkyO2sVzOmKlE4ruY/wOrYyGJpdmSONq hh9MK7RfMTxq2oSPtagrIA4w08IU9IAfsiVSoL0ltzVqt7Y4cwEiOAbf8gMv+MW7oRFOEt2QR6p8W exIgmTyQ3vjEklsvKX+MqLV7XLdznzVvxBvh83wNUhcLWGg00+VjG05j/vFYveym5TL9wt5OiWzPY LzFK0CasoGNA+gOGW4UA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1g7KXu-0008Bw-DT; Tue, 02 Oct 2018 13:17:02 +0000 Received: from mail-wm1-x342.google.com ([2a00:1450:4864:20::342]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1g7KU2-0005MG-2H for linux-arm-kernel@lists.infradead.org; Tue, 02 Oct 2018 13:13:15 +0000 Received: by mail-wm1-x342.google.com with SMTP id s12-v6so2220585wmc.0 for ; Tue, 02 Oct 2018 06:12:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=UwxTkI+pYsHu40iHWOY4wB/R27fPZGDmoFBeZbslwgQ=; b=uOQ+FfmUC+RaS3QyuW/9cJe9RH7pk1ltGJ/08pMGtCZU0scrsbZfvGCfzNFlnYWeR5 g4Vr9xESUkQ3uzvvWZq0xdqiM4GWXtOzvpTeiJAGBAFrgtHYW5APJNvA76dSQYg6AQ6U +HnGxnOWKMtPLutPQOCuJNs520+lOBa8RK6H5554UVrF0vYcw9e7fDpm51uyEaclf9he mlrY9jl92q9OeuR3mYmCoOs+LQInROEeHRG03TikcJ97tIw0t2mAJ68JeLA3lwRgRJ8x Pq5kHnJz2EmX3aXhV7wv8Shr2/YuRwwklttZlbsqxMfB4W5wvp501g+TByqSV28przNS TNVw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=UwxTkI+pYsHu40iHWOY4wB/R27fPZGDmoFBeZbslwgQ=; b=udIggTtKsW9EWrXui0U7dQ8RGiXAlcBI2smPSs1zozeiDTboR2uofW08jf0mERN6Pv vHET0oqSUuCdl9Y/7jHduooBySSc7+BR20/PxlJz2wKUB+zsfwMNoPf1dsQZdGziuMrr iB6ksfuKJGLhf9tDj42mcqpxU2QQQrd05orVwTEjRXa13k+EvptEM++zt9RAVJVDrpO+ A3nRaJIZWvgxtorQR/DWFzrdA0RE18f7M2mi1Ws+XEvcA8pfbavCrxQ3ojmkGXg5DHr/ EAbQQFoeVVZXHCG7W3NqVEUPBo/6iyKcyFb1d9Fu8Bb5CuOyDf+uU96VAoXep7fNo2/N +KwQ== X-Gm-Message-State: ABuFfohyfRhZbPGSggneyz38PCKlY4q9BVC59oT51g+sNQ4UF2BntAnE S0wpRt1Ae4My0jhB4VHtWU1VMg== X-Google-Smtp-Source: ACcGV622sDyFt3S8csEmXThpDBNFNMvaRauKoxqXv/A4k50G/uwAP10xj9S7JvVx/Gl6W/hzjmgNeA== X-Received: by 2002:a1c:d4b:: with SMTP id 72-v6mr1969892wmn.102.1538485970324; Tue, 02 Oct 2018 06:12:50 -0700 (PDT) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:10:84be:a42a:826d:c530]) by smtp.gmail.com with ESMTPSA id v10-v6sm17458681wrp.0.2018.10.02.06.12.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 02 Oct 2018 06:12:49 -0700 (PDT) From: Andrey Konovalov To: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v7 3/8] arm64: untag user addresses in access_ok and __uaccess_mask_ptr Date: Tue, 2 Oct 2018 15:12:38 +0200 Message-Id: <2b957e4f0a3133480dda9d9c8aeceb9b9d9378eb.1538485901.git.andreyknvl@google.com> X-Mailer: git-send-email 2.19.0.605.g01d371f741-goog In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181002_061302_146764_5AB69535 X-CRM114-Status: GOOD ( 14.60 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Chintan Pandya , Jacob Bramley , Ruben Ayrapetyan , Andrey Konovalov , Lee Smith , Kostya Serebryany , Dmitry Vyukov , Ramana Radhakrishnan , Luc Van Oostenryck , Evgeniy Stepanov Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP copy_from_user (and a few other similar functions) are used to copy data from user memory into the kernel memory or vice versa. Since a user can provided a tagged pointer to one of the syscalls that use copy_from_user, we need to correctly handle such pointers. Do this by untagging user pointers in access_ok and in __uaccess_mask_ptr, before performing access validity checks. Signed-off-by: Andrey Konovalov --- arch/arm64/include/asm/uaccess.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 2d6451cbaa86..fa7318d3d7d5 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -105,7 +105,8 @@ static inline unsigned long __range_ok(const void __user *addr, unsigned long si #define untagged_addr(addr) \ ((__typeof__(addr))sign_extend64((__u64)(addr), 55)) -#define access_ok(type, addr, size) __range_ok(addr, size) +#define access_ok(type, addr, size) \ + __range_ok(untagged_addr(addr), size) #define user_addr_max get_fs #define _ASM_EXTABLE(from, to) \ @@ -237,7 +238,8 @@ static inline void uaccess_enable_not_uao(void) /* * Sanitise a uaccess pointer such that it becomes NULL if above the - * current addr_limit. + * current addr_limit. In case the pointer is tagged (has the top byte set), + * untag the pointer before checking. */ #define uaccess_mask_ptr(ptr) (__typeof__(ptr))__uaccess_mask_ptr(ptr) static inline void __user *__uaccess_mask_ptr(const void __user *ptr) @@ -245,10 +247,11 @@ static inline void __user *__uaccess_mask_ptr(const void __user *ptr) void __user *safe_ptr; asm volatile( - " bics xzr, %1, %2\n" + " bics xzr, %3, %2\n" " csel %0, %1, xzr, eq\n" : "=&r" (safe_ptr) - : "r" (ptr), "r" (current_thread_info()->addr_limit) + : "r" (ptr), "r" (current_thread_info()->addr_limit), + "r" (untagged_addr(ptr)) : "cc"); csdb();