From patchwork Thu Aug 13 15:32:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Garzarella X-Patchwork-Id: 11712609 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 2C2AF109B for ; Thu, 13 Aug 2020 15:34:00 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 7ECC020781 for ; Thu, 13 Aug 2020 15:33:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XAWewq3B" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7ECC020781 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-19625-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 13362 invoked by uid 550); 13 Aug 2020 15:33:58 -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 13342 invoked from network); 13 Aug 2020 15:33:57 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1597332825; 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=U+DZxetMKI4jVQKv/cLX0z4HNCC6l+3oyJGtLYHcX8o=; b=XAWewq3B9ffElLPLK8aqXEdtA0lEYNv0TEcNPEvzuPpuKkqxxXovnF9IBkamQqxqnwOH5d vbaiYgvvqm0SkxTxkI0w1i/SA50l6SAEi0TPTa0z0WXMiD5c3dNd4H8VCRVQTV4MerO89+ qCIVor4oyVizlmurC+dje/EROwsSDUU= X-MC-Unique: rFiyPInxM7CpmkqnLbRD4g-1 From: Stefano Garzarella To: Jens Axboe Cc: Christian Brauner , Jann Horn , Jeff Moyer , linux-fsdevel@vger.kernel.org, Sargun Dhillon , Kees Cook , Alexander Viro , Kernel Hardening , Stefan Hajnoczi , linux-kernel@vger.kernel.org, Aleksa Sarai , io-uring@vger.kernel.org Subject: [PATCH v4 0/3] io_uring: add restrictions to support untrusted applications and guests Date: Thu, 13 Aug 2020 17:32:51 +0200 Message-Id: <20200813153254.93731-1-sgarzare@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 v4: - rebased on top of io_uring-5.9 - fixed io_uring_enter() exit path when ring is disabled v3: https://lore.kernel.org/io-uring/20200728160101.48554-1-sgarzare@redhat.c= om/ RFC v2: https://lore.kernel.org/io-uring/20200716124833.93667-1-sgarzare@redh= at.com RFC v1: https://lore.kernel.org/io-uring/20200710141945.129329-1-sgarzare@red= hat.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@steredha= t/ 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 | 160 ++++++++++++++++++++++++++++++++-- include/uapi/linux/io_uring.h | 60 ++++++++++--- 2 files changed, 203 insertions(+), 17 deletions(-) --=20 2.26.2