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: 11689473 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 61A1714B7 for ; Tue, 28 Jul 2020 16:01:39 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 6FDE02053B for ; Tue, 28 Jul 2020 16:01:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="a7u4Uj2X" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6FDE02053B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19468-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 23751 invoked by uid 550); 28 Jul 2020 16:01:36 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 23725 invoked from network); 28 Jul 2020 16:01:35 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595952083; 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=a7u4Uj2XLJFASyhrlsZW4U/0nnK2PUI/BVLTFClQDauxOoFaSfTOTiOC+UaRClweUEYT/E ih6NsZubfd2f/y+Oszl0iBZ55X/kCr/QuJnuLTHJYT/N5CNCdLN/cE+wxnCSeBxLZm6RTg 0XROEqEYO0tNr5LDV7ciFRZCP1fSWDo= X-MC-Unique: JNkooa47PDmLLs1bZyICfw-1 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 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(-)