From patchwork Tue Apr 30 13:24:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10923465 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 B62AC933 for ; Tue, 30 Apr 2019 13:25:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A6806285EB for ; Tue, 30 Apr 2019 13:25:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9950B28A63; Tue, 30 Apr 2019 13:25:31 +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=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3E64C285EB for ; Tue, 30 Apr 2019 13:25:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728154AbfD3NZ3 (ORCPT ); Tue, 30 Apr 2019 09:25:29 -0400 Received: from mail-vk1-f202.google.com ([209.85.221.202]:56200 "EHLO mail-vk1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728055AbfD3NZ2 (ORCPT ); Tue, 30 Apr 2019 09:25:28 -0400 Received: by mail-vk1-f202.google.com with SMTP id z6so6312555vkf.22 for ; Tue, 30 Apr 2019 06:25:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=BvUTfQkQM7uCDeEtImKKI/2Hme2ZprNLcMmbkGV4djo=; b=dpVTwFKbchbVkkb84ng8BnoHNS2SM91wquNJtuly6Sbp7lXj1bPrbJBiP3SyhTU0xP LuA/DNrbjhKI/dHi3IXFK1lS8O09Sk1+qA/R7rjDLupO2W7Szy3T1dELXK4hEpZqkwPw qD0yKLxb8ZjzpYALNjI1z0dDf4TB8V0IRIOptCx1gDVu9+jOblt+XzKkwvlPuV63pqHj wnFsYt5mNXo/Rj6N9Lo9JMQODsljOWPF/MJrAcRLfdznXkGZCgNmaSrk7MrXtOUREZGb X2QTJ1/W011vEIe5OofpK81AMWPuQy4lXPQltspauNse0OruElYuf2mJ90h6FolZJ8lL VpnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=BvUTfQkQM7uCDeEtImKKI/2Hme2ZprNLcMmbkGV4djo=; b=Or2w8bBU5tzbq/Qx7+6yT3bN7jCnNz7awseTUk2rpqdw9UmddORQKkbwFUn0pJ3Qdi itZvkXkzbSL3J9c7s5Op4cHOxl3m8Uu7wBrojxv8PFKMoVJvpAhtBHUEivDi2SANwW1H wmft8L0xqTL37GY/eHUcoTdLz3xhzAGtz3QhzGcIh9PN5xkIxMLiWmRvO9zrtOVxykVe Se9WrxtJTqtaq9w3l5tyE/cZ/oZGNP6/8qYm6ybtquA6PnREi1DyKjndw+3FaMbJeLdc HMJl9cfmV261W2llRjCWaYjzd2W9xBUP2PtG7AZP1IfKSyZ9OP/KQ07JtSKrJ2Qi07m+ 14wA== X-Gm-Message-State: APjAAAUuO+Wk8ReBnOVNvUL0cAXtas3vjMOZuJpMc8N7QyULCH4vdw58 OV5DzTZKB2s1G6tdfIwHdGlV3rKjgt+945Yf X-Google-Smtp-Source: APXvYqyRA/Qu4LKAWcvJoaQQlsyyIllouYjqkXgAFh5vrZ+95OMG6R4QdBb3NSzDXJSn7wdUrbj4M88LAp+D5Hqp X-Received: by 2002:a67:ea83:: with SMTP id f3mr2107513vso.59.1556630726654; Tue, 30 Apr 2019 06:25:26 -0700 (PDT) Date: Tue, 30 Apr 2019 15:24:59 +0200 In-Reply-To: Message-Id: <6f38f610cc22dca9aef05d53a5a94b24763cc628.1556630205.git.andreyknvl@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.21.0.593.g511ec345e18-goog Subject: [PATCH v14 03/17] lib, arm64: untag user pointers in strn*_user From: Andrey Konovalov To: linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Catalin Marinas , Vincenzo Frascino , Will Deacon , Mark Rutland , Andrew Morton , Greg Kroah-Hartman , Kees Cook , Yishai Hadas , Kuehling@google.com, Felix , Deucher@google.com, Alexander , Koenig@google.com, Christian , Mauro Carvalho Chehab , Jens Wiklander , Alex Williamson , Leon Romanovsky , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Robin Murphy , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy , Andrey Konovalov Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch is a part of a series that extends arm64 kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments. strncpy_from_user and strnlen_user accept user addresses as arguments, and do not go through the same path as copy_from_user and others, so here we need to handle the case of tagged user addresses separately. Untag user pointers passed to these functions. Note, that this patch only temporarily untags the pointers to perform validity checks, but then uses them as is to perform user memory accesses. Signed-off-by: Andrey Konovalov --- lib/strncpy_from_user.c | 3 ++- lib/strnlen_user.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c index 58eacd41526c..6209bb9507c7 100644 --- a/lib/strncpy_from_user.c +++ b/lib/strncpy_from_user.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include @@ -107,7 +108,7 @@ long strncpy_from_user(char *dst, const char __user *src, long count) return 0; max_addr = user_addr_max(); - src_addr = (unsigned long)src; + src_addr = (unsigned long)untagged_addr(src); if (likely(src_addr < max_addr)) { unsigned long max = max_addr - src_addr; long retval; diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c index 1c1a1b0e38a5..8ca3d2ac32ec 100644 --- a/lib/strnlen_user.c +++ b/lib/strnlen_user.c @@ -2,6 +2,7 @@ #include #include #include +#include #include @@ -109,7 +110,7 @@ long strnlen_user(const char __user *str, long count) return 0; max_addr = user_addr_max(); - src_addr = (unsigned long)str; + src_addr = (unsigned long)untagged_addr(str); if (likely(src_addr < max_addr)) { unsigned long max = max_addr - src_addr; long retval;