From patchwork Mon May 6 16:30:49 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10931549 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 6999215A6 for ; Mon, 6 May 2019 16:33:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 58A4228847 for ; Mon, 6 May 2019 16:33:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4C4BC28848; Mon, 6 May 2019 16:33:30 +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 E13A328864 for ; Mon, 6 May 2019 16:33:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726827AbfEFQbS (ORCPT ); Mon, 6 May 2019 12:31:18 -0400 Received: from mail-yw1-f74.google.com ([209.85.161.74]:49935 "EHLO mail-yw1-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726754AbfEFQbR (ORCPT ); Mon, 6 May 2019 12:31:17 -0400 Received: by mail-yw1-f74.google.com with SMTP id v123so26346243ywf.16 for ; Mon, 06 May 2019 09:31:17 -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=x8HMVSO2lCP9thpVq0jteC8wa+ruR/qG5sfvMEzcSf4=; b=e90YIYJEqCjuv0dQNXe7JfByZ3LYw/uoix1gLG6qHxakrZEGoit4yh6fTDsfYia+jH wb7igUzrFQvpjJl955zqS3eb64AMNM806CURkcixGS6z1rzCJzMGBiAz82rRhlhjgKjR 9cdDyeo/3JMugM0eGAxc56H2X/rF/Gu5NZJ6OlTvycYfBxRjWeovYDz5GGyc2/popU6X Q4rJTvbhNlqr5zqGtmKCjWUttV6dsKWcbk2qBw0aV1In8VLH8mRF5MiPk8iCO4KWMnPF BSI3N1BBXtSHWlnz3+Iji+1TK5JldUspg0pnnlvUCK4PaDa6c2GsK9cElOVCY5yx3kNx bcTw== 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=x8HMVSO2lCP9thpVq0jteC8wa+ruR/qG5sfvMEzcSf4=; b=LHUIEcAxYuSaOC63o4QeOMP6zg6Z89LInD8zRdQ9UFE2T/gYjDwsuMbb6See4lICkD V3Uqq9cTTZ78BO8AXPCFgJ2DzTQLLXXhGJ4a1UG5jhrQmN2B8ig32Wo3ZW5KUp7n55Lj v7NZKfWDPPd2g26sMN0uzvPhTNGfOTxpJfQL66FI3wR9JwNkYxbQ57SZ6MVUSj9lY4fG WJ3xWmMLeJaQJNki7tYeUYMYjX/HGXacm8mbuB/xn2YldF+haaGtxPwID/j2M0vRUSqr +7nPpTvCi6tlBtHoLk/RrD95s0OQSM475znaHneg48dfQQmgf1aVJOEXoZLSEdBWMcIu tbzw== X-Gm-Message-State: APjAAAXCQoKan16CoV8YfshVPrwweC2v3DLaAMwjfgRzYnhqwkbs3gzj fjFvFhsCDBIczVFnaGsx4T8P1CI3YEiC4Iga X-Google-Smtp-Source: APXvYqyZq8rlWFW4uBLN8C8I3oEaQAU5CNW3HReq+6c5opQ9wp/VGDDqgMMeEo6tOAWNlA3+Gfl3rFVlDcMv6bDq X-Received: by 2002:a5b:8c2:: with SMTP id w2mr16278460ybq.201.1557160276487; Mon, 06 May 2019 09:31:16 -0700 (PDT) Date: Mon, 6 May 2019 18:30:49 +0200 In-Reply-To: Message-Id: <861418ff7ed7253356cb8267de5ee2d4bd84196d.1557160186.git.andreyknvl@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog Subject: [PATCH v15 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 , Felix Kuehling , Alexander Deucher , Christian Koenig , 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 , 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 Reviewed-by: Catalin Marinas --- 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;