From patchwork Mon Jun 3 16:55:08 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10973429 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 64F776C5 for ; Mon, 3 Jun 2019 16:57:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 509CB28658 for ; Mon, 3 Jun 2019 16:57:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 444ED2873A; Mon, 3 Jun 2019 16:57:47 +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 E3DDD28658 for ; Mon, 3 Jun 2019 16:57:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726272AbfFCQ5p (ORCPT ); Mon, 3 Jun 2019 12:57:45 -0400 Received: from mail-qt1-f201.google.com ([209.85.160.201]:39592 "EHLO mail-qt1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729547AbfFCQzo (ORCPT ); Mon, 3 Jun 2019 12:55:44 -0400 Received: by mail-qt1-f201.google.com with SMTP id o16so8102604qtj.6 for ; Mon, 03 Jun 2019 09:55:43 -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=8pgHCk5wEiyaTFCxwJKfncM1f+2WF9g+TqLFqNfWufQ=; b=eM3yvxS7rzZ2nnFYrRtwMpVwIimBA7OeBVGUKG05qqQOYpi+Zis4iOHoCqOn+3sjDh 2SabES8eFCAsnon36EZg8qxjmj+CW/08eSPui+O8M8q9qj9EihXzk/kg7mFnv1ofmO2L 6gdrPpvdTVeWEXirSohkSFcGd3CTquZjzaE1d3uIrVhOjCiqBdkigRuAKI8/ID1Mi6ud zk8tRRsd3G4px7QGEmRqWs1oq4KZBZQ84TPIW2/PRqcP/P9TeozrBt0HPw3seUNx6jqU wgzokqzg3Z9TB08A/q6k7ggwnJy6GtgW83uc4Qh4qCVWwdITo0WCqdd0x9WCtndSuvUL /u8A== 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=8pgHCk5wEiyaTFCxwJKfncM1f+2WF9g+TqLFqNfWufQ=; b=uJpGBgRgIiuZzZKv8YfOkgxRawJOV3GtdqQFf/I29n5kgyHtWLyKxpCncoIfl+EU3c Ed1DD1327HFG96yHQHv9ol1QZk+TFRTcqAE5PjqOvucpePv8ptiBepHw77Xm/2XAXSeL UG+vWZCAEKYSm0vZEHhVx7b0kX+pwnQC1y2mIkfCAgv7awuSVkwzK1Un27QYn2T4KHJc aQH655wBGIyCb+FET8wwt3kaGo0uu+KWmj0zBAO1iU0TGAL0vMSwWjG/YyVSUk+3iS6r wKviF/srlyClvX9XYpuPcQtvq5BWCT8x+niDSTz7yZMYanuVshYTSNnryNLuAEUWXtKc hB7g== X-Gm-Message-State: APjAAAVBl+ZSpP6AYPH08MQQYp8M1wk+yL8SPBpMbr0cmErtUZ5dNxzg rdlB7gOq8wif1Qh7RRBcFfIq0VKBtGBaZBDW X-Google-Smtp-Source: APXvYqyNatgo8rHVRn4VlhemarHIUF3AdcvyBy1EVpeL8RHKUhqmEsOqMc7TMbe6ArCDJ95BM6gVWf7qKnPTt9YN X-Received: by 2002:a0c:9233:: with SMTP id a48mr6236042qva.66.1559580942841; Mon, 03 Jun 2019 09:55:42 -0700 (PDT) Date: Mon, 3 Jun 2019 18:55:08 +0200 In-Reply-To: Message-Id: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.22.0.rc1.311.g5d7573a151-goog Subject: [PATCH v16 06/16] mm, arm64: untag user pointers in mm/gup.c 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 , Luc Van Oostenryck , Dave Martin , Khalid Aziz , enh , Jason Gunthorpe , Christoph Hellwig , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Robin Murphy , Kevin Brodsky , Szabolcs Nagy , Andrey Konovalov Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@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. mm/gup.c provides a kernel interface that accepts user addresses and manipulates user pages directly (for example get_user_pages, that is used by the futex syscall). Since a user can provided tagged addresses, we need to handle this case. Add untagging to gup.c functions that use user addresses for vma lookups. Reviewed-by: Catalin Marinas Signed-off-by: Andrey Konovalov Reviewed-by: Kees Cook --- mm/gup.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/gup.c b/mm/gup.c index ddde097cf9e4..c37df3d455a2 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -802,6 +802,8 @@ static long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, if (!nr_pages) return 0; + start = untagged_addr(start); + VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET)); /* @@ -964,6 +966,8 @@ int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm, struct vm_area_struct *vma; vm_fault_t ret, major = 0; + address = untagged_addr(address); + if (unlocked) fault_flags |= FAULT_FLAG_ALLOW_RETRY;