From patchwork Wed Jun 12 11:43:25 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10989633 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 C668B14C0 for ; Wed, 12 Jun 2019 11:45:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B4730286C6 for ; Wed, 12 Jun 2019 11:45:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A553728A24; Wed, 12 Jun 2019 11:45:06 +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 0AFB5286C6 for ; Wed, 12 Jun 2019 11:45:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2438585AbfFLLpA (ORCPT ); Wed, 12 Jun 2019 07:45:00 -0400 Received: from mail-vs1-f73.google.com ([209.85.217.73]:48756 "EHLO mail-vs1-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2438457AbfFLLoD (ORCPT ); Wed, 12 Jun 2019 07:44:03 -0400 Received: by mail-vs1-f73.google.com with SMTP id i6so5309575vsp.15 for ; Wed, 12 Jun 2019 04:44:02 -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=0pRrtQh1WGSItgbOKTKHJXYw3ig9cf9ovTOOwQBNCxo=; b=IoAMjSO8LpV9sQ4rhyGuwSi9qAWnWdJKm92qjIFlDfIzZK27lRdtbBpUTTqSsHKQqq mk4pY6s02uPltexkWHMnxfPS6E14WpHQTBtMuXD5ciPLmKwQYfFZ7D/irHKINjpULcIC qesPb2LJHGU1U+hg3Lnr8sbHR2PLa6XJRSA+MwutfJ1QD1fm8gchvdk4JFKcehQpLj7U rwlJqHzorntg7c/BDSuoHH78gq9KnzX7dlAs2pxjWc6C1dDkPCqTKTM+gMG73nj/ByrG HBTS6w/3UTjUct6MrDb5Sf2LP5/PYv9l52cM1MNahSes/06CDdeCzTIAFl18VFOFWLlP HuBg== 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=0pRrtQh1WGSItgbOKTKHJXYw3ig9cf9ovTOOwQBNCxo=; b=lG3v1CwdqM4FhKuwBk0aG91nm6Y7vEQL009GvfVZ95lZR1tTdB59vlMfufwSSQxBRm GXBm+7YfSi1IPchl6gAFY4Uur8YkkazUFR3cSzkUUwtl8AeiW2VrZHmdn/FunYYl0V4N Y35xPmBPk3C5T4+JXZLyGihxyh676WRUKoj313pmFGORu76Y7G6MQTM2UyQwwsueOVjw yvdj2lZwPUP8pIEs8KmTD+r45BknhjKGUExbs3l9zxWaYVTTZHY7ohUQpVRf3R+yqWPI KXp4McBRUXo5GprZFeSX8Gj6sQMZQXXlfZB+d0UwhJEWJY0HSvKt4L3dRmVY99rt1qc7 KSUA== X-Gm-Message-State: APjAAAUZzXSlyWu/KCfVXHGewlyMOf+cFYT1aerH06xneaYCiSPF/U1y W84l82G1Qa9qNkhNqAGJkKR9Cwo17WovGIqf X-Google-Smtp-Source: APXvYqyhjQEo4g9YND5Fe8F9dcUypnQYf8jfozQHANwshchy+6+kG6ludLuigCmoO08U0FojfDlhn98Rsb9Khi5b X-Received: by 2002:a9f:25e9:: with SMTP id 96mr28666032uaf.95.1560339842024; Wed, 12 Jun 2019 04:44:02 -0700 (PDT) Date: Wed, 12 Jun 2019 13:43:25 +0200 In-Reply-To: Message-Id: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.22.0.rc2.383.gf4fbbf30c2-goog Subject: [PATCH v17 08/15] userfaultfd, arm64: untag user pointers 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: 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. userfaultfd code use provided user pointers for vma lookups, which can only by done with untagged pointers. Untag user pointers in validate_range(). Reviewed-by: Catalin Marinas Reviewed-by: Kees Cook Signed-off-by: Andrey Konovalov Reviewed-by: Vincenzo Frascino --- 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;