From patchwork Tue Jul 28 16:00:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Garzarella X-Patchwork-Id: 11689471 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4BB3814B7 for ; Tue, 28 Jul 2020 16:01:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31C90207F5 for ; Tue, 28 Jul 2020 16:01:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="MTBCNFvU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730821AbgG1QB2 (ORCPT ); Tue, 28 Jul 2020 12:01:28 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:59747 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1731176AbgG1QBZ (ORCPT ); Tue, 28 Jul 2020 12:01:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595952084; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=0fc1uAttsGy8w1em246ZebEdbW8vUt+X7/u6oIFpaS0=; b=MTBCNFvUe4/uZ7qwXhVRKam7rtDay6GM224dcpEZLVunXzTwdum6/JzbJyqnSMT0veqh2y IL6X1W2rkG5QCH7OJeZIo6m2bkCpZZVKlEHvVFtbsMDQ+uk4p608/pSxckv3hy7De4or1Z /X2hK36HTXr4nXBWu86CWOb1O72b85w= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-365-JNkooa47PDmLLs1bZyICfw-1; Tue, 28 Jul 2020 12:01:20 -0400 X-MC-Unique: JNkooa47PDmLLs1bZyICfw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9CCA419200D5; Tue, 28 Jul 2020 16:01:18 +0000 (UTC) Received: from steredhat.redhat.com (ovpn-112-109.ams2.redhat.com [10.36.112.109]) by smtp.corp.redhat.com (Postfix) with ESMTP id C1C475D9CD; Tue, 28 Jul 2020 16:01:02 +0000 (UTC) From: Stefano Garzarella To: Jens Axboe Cc: io-uring@vger.kernel.org, Alexander Viro , Kees Cook , Jeff Moyer , Kernel Hardening , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Aleksa Sarai , Sargun Dhillon , Stefan Hajnoczi , Christian Brauner , Jann Horn Subject: [PATCH v3 0/3] io_uring: add restrictions to support untrusted applications and guests Date: Tue, 28 Jul 2020 18:00:58 +0200 Message-Id: <20200728160101.48554-1-sgarzare@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org v3: - added IORING_RESTRICTION_SQE_FLAGS_ALLOWED and IORING_RESTRICTION_SQE_FLAGS_REQUIRED - removed IORING_RESTRICTION_FIXED_FILES_ONLY opcode - enabled restrictions only when the rings start RFC v2: https://lore.kernel.org/io-uring/20200716124833.93667-1-sgarzare@redhat.com RFC v1: https://lore.kernel.org/io-uring/20200710141945.129329-1-sgarzare@redhat.com Following the proposal that I send about restrictions [1], I wrote this series to add restrictions in io_uring. I also wrote helpers in liburing and a test case (test/register-restrictions.c) available in this repository: https://github.com/stefano-garzarella/liburing (branch: io_uring_restrictions) Just to recap the proposal, the idea is to add some restrictions to the operations (sqe opcode and flags, register opcode) to safely allow untrusted applications or guests to use io_uring queues. The first patch changes io_uring_register(2) opcodes into an enumeration to keep track of the last opcode available. The second patch adds IOURING_REGISTER_RESTRICTIONS opcode and the code to handle restrictions. The third patch adds IORING_SETUP_R_DISABLED flag to start the rings disabled, allowing the user to register restrictions, buffers, files, before to start processing SQEs. Comments and suggestions are very welcome. Thank you in advance, Stefano [1] https://lore.kernel.org/io-uring/20200609142406.upuwpfmgqjeji4lc@steredhat/ Stefano Garzarella (3): io_uring: use an enumeration for io_uring_register(2) opcodes io_uring: add IOURING_REGISTER_RESTRICTIONS opcode io_uring: allow disabling rings during the creation fs/io_uring.c | 167 ++++++++++++++++++++++++++++++++-- include/uapi/linux/io_uring.h | 60 +++++++++--- 2 files changed, 207 insertions(+), 20 deletions(-)