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,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 AEC8CC28D17 for ; Mon, 3 Jun 2019 16:55:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 88AA327426 for ; Mon, 3 Jun 2019 16:55:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Ic80Nhco" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729646AbfFCQz6 (ORCPT ); Mon, 3 Jun 2019 12:55:58 -0400 Received: from mail-qk1-f202.google.com ([209.85.222.202]:41051 "EHLO mail-qk1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729618AbfFCQzz (ORCPT ); Mon, 3 Jun 2019 12:55:55 -0400 Received: by mail-qk1-f202.google.com with SMTP id o4so984139qko.8 for ; Mon, 03 Jun 2019 09:55:53 -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=V8W9/R1INxLH8IpjzMBaweiOjVPk4ghaGGjHQk6nF0Q=; b=Ic80Nhco3iRVjaadOA8+znksGsevCWKjr0xS5FrfRT68EY2GjH7FNqxQ/S059IWRME Uk1bw3K6alaW8N/9Rs9bh2+EZh8EcVJH3cxi1ame2GYHVGzkN7Qz1H1smlWX23XCNo3x XPf9GSBwjp2Wlg5+Uj+WrIp+Jk7K9IWrhUgFda1FHXXV316C7cTRBKd5zQOn+A1+5Aft F1iszJDrA1FKS5eHvaL17A52p/3BNscmam9+VyXB7pU/EsAF/YnBaqcEkTUbGMZM4HOi O4Y2Ewn60j/2WNgR2OxufWSoY1qQbeSPNPwvgeO0aN1frIK5bxzhsw5VzJiPVQL++TeN 2Fgw== 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=V8W9/R1INxLH8IpjzMBaweiOjVPk4ghaGGjHQk6nF0Q=; b=BaHywj5kZfEviUgDBLBlE3ZZSM2JzyBUSggWwFGo6CY7vxOFkVK1wpot+kozzijV20 vbeSv7LI21V7eXVc9/Gzwiktkn8rIqSs4ONqUfgjyeGVve3xnMLk6F+LZBwmzmMr3m1u CXdpSNsk9ggMN1xAFZI+oqeaMpxqUClsOwqysEZbWg0nJL6APHr9GGbgwgJFg81ZmR5A KHFAolC+wh1+tRvVzag9hs/xpD/atQe3fqmHMBKiZZ68yHcNpfNY235yrLZhxMiJaNJK q9kFuNwBAar2oloJk31M9fZ3Ff8wG1pNB4cEpjubYZ+jXRoNXRhvdTXqm6Gh5Vq1Kz93 bBVA== X-Gm-Message-State: APjAAAVE6iN4PIsDaR+bou8ThFDCgJ0dXKR7OMRkoqE8cJJutMaVL6hx IAD1RDS5Bjmv7RUIyVpiVyaMr99oHAoqqzbZ X-Google-Smtp-Source: APXvYqxbJDGUw94i6RNaa88fy33raOhr5MIqE66YRUj/nWlTewQjYqVQIrvYFblxs7ri2FDDMOtmRTjTXzyL1IBV X-Received: by 2002:a37:6782:: with SMTP id b124mr6422877qkc.242.1559580953075; Mon, 03 Jun 2019 09:55:53 -0700 (PDT) Date: Mon, 3 Jun 2019 18:55:11 +0200 In-Reply-To: Message-Id: <7d6fef00d7daf647b5069101da8cf5a202da75b0.1559580831.git.andreyknvl@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.22.0.rc1.311.g5d7573a151-goog Subject: [PATCH v16 09/16] fs, arm64: untag user pointers in fs/userfaultfd.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. userfaultfd code use provided user pointers for vma lookups, which can only by done with untagged pointers. Untag user pointers in validate_range(). Signed-off-by: Andrey Konovalov --- fs/userfaultfd.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 3b30301c90ec..24d68c3b5ee2 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1263,21 +1263,23 @@ static __always_inline void wake_userfault(struct userfaultfd_ctx *ctx, } static __always_inline int validate_range(struct mm_struct *mm, - __u64 start, __u64 len) + __u64 *start, __u64 len) { __u64 task_size = mm->task_size; - if (start & ~PAGE_MASK) + *start = untagged_addr(*start); + + if (*start & ~PAGE_MASK) return -EINVAL; if (len & ~PAGE_MASK) return -EINVAL; if (!len) return -EINVAL; - if (start < mmap_min_addr) + if (*start < mmap_min_addr) return -EINVAL; - if (start >= task_size) + if (*start >= task_size) return -EINVAL; - if (len > task_size - start) + if (len > task_size - *start) return -EINVAL; return 0; } @@ -1327,7 +1329,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx, goto out; } - ret = validate_range(mm, uffdio_register.range.start, + ret = validate_range(mm, &uffdio_register.range.start, uffdio_register.range.len); if (ret) goto out; @@ -1516,7 +1518,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx, if (copy_from_user(&uffdio_unregister, buf, sizeof(uffdio_unregister))) goto out; - ret = validate_range(mm, uffdio_unregister.start, + ret = validate_range(mm, &uffdio_unregister.start, uffdio_unregister.len); if (ret) goto out; @@ -1667,7 +1669,7 @@ static int userfaultfd_wake(struct userfaultfd_ctx *ctx, if (copy_from_user(&uffdio_wake, buf, sizeof(uffdio_wake))) goto out; - ret = validate_range(ctx->mm, uffdio_wake.start, uffdio_wake.len); + ret = validate_range(ctx->mm, &uffdio_wake.start, uffdio_wake.len); if (ret) goto out; @@ -1707,7 +1709,7 @@ static int userfaultfd_copy(struct userfaultfd_ctx *ctx, sizeof(uffdio_copy)-sizeof(__s64))) goto out; - ret = validate_range(ctx->mm, uffdio_copy.dst, uffdio_copy.len); + ret = validate_range(ctx->mm, &uffdio_copy.dst, uffdio_copy.len); if (ret) goto out; /* @@ -1763,7 +1765,7 @@ static int userfaultfd_zeropage(struct userfaultfd_ctx *ctx, sizeof(uffdio_zeropage)-sizeof(__s64))) goto out; - ret = validate_range(ctx->mm, uffdio_zeropage.range.start, + ret = validate_range(ctx->mm, &uffdio_zeropage.range.start, uffdio_zeropage.range.len); if (ret) goto out; -- 2.22.0.rc1.311.g5d7573a151-goog