From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_MED,URIBL_BLOCKED, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5982C04AB5 for ; Mon, 3 Jun 2019 16:55:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F4FA274CD for ; Mon, 3 Jun 2019 16:55:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="eM3yvxS7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729568AbfFCQzo (ORCPT ); Mon, 3 Jun 2019 12:55:44 -0400 Received: from mail-qk1-f201.google.com ([209.85.222.201]:42998 "EHLO mail-qk1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729545AbfFCQzn (ORCPT ); Mon, 3 Jun 2019 12:55:43 -0400 Received: by mail-qk1-f201.google.com with SMTP id l16so991976qkk.9 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=HoB8ABQWyeYLc5NFTx9iwAsoIxmKPvfdIW2XZMJSCtlZeV5s8wu+FTmTpOYrHIeQrd ivTpyx3JD8eC10FZUEFUYYI4lCQICB/tJ1dtKQAr0WgMXChKS4zdjeaCdwj0ToXpPsfY thWWdRPWOrXl2hrE9Hn+t4g50S/QvToioUlm5fYhrGNB6SZJ6YCJRahFmntyY7H+cknU eePsS5nPqB7HJ7xn1gn9jFmcoJ6w4PRiNGYzFNWRYYEXmJra/nJ6rlKXh6AWbWfqbN2J yK5eWmm3Q+ptdsddyFcoeTvsCEGITHbyZYpz4PTRvQ/PWTN2GOK+LdFxe/b1rj/+tPtW u4lA== X-Gm-Message-State: APjAAAXcxPtNOrCJvpZDpIS5nm/wO1I90bAs8g1G3dnczgb1Q4/1SYRo 6wbK136/QCGH0DywMdZAtJxoq6sdJsqSM6y4 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 Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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; -- 2.22.0.rc1.311.g5d7573a151-goog