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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 18D5BC433E1 for ; Mon, 17 Aug 2020 06:38:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E47C020716 for ; Mon, 17 Aug 2020 06:38:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="GB71ygqQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726773AbgHQGiC (ORCPT ); Mon, 17 Aug 2020 02:38:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726746AbgHQGiA (ORCPT ); Mon, 17 Aug 2020 02:38:00 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA27FC061388; Sun, 16 Aug 2020 23:37:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=vFCbJ3ug2U1sY/t9JxVGfwsBp7E2ZDBnSzqrL0yKU6g=; b=GB71ygqQK5AcFDF6QOiadRELSn IwohiW6Xy3vy1LevaEoifMeosAWzkp36zJlfX8w6/kLEePZCDfLHmuTmg3o0yY08Zgt6T2DNAHd8I BaomfyuiRnjM9PEAaaA/qaNMz3Ru/f04dmi3k5Dq9K/LLp+HhlgJxM97II2qWCGhfoE8j50nk+Gjt GXpk4QOiklF+N8C+vFEKkkG7CrecHzMkap9LOAz49xYUtUHyvBFG905ksG0+1Nh0gpD7Bb1dw6DVp wd7QRAt96+bO9LvbC0Rc8el2Kvvcfa/HRjAg0WkforfS+IhQ7x0QTrXJ8/FO+rpW9eJSAb37JxkYx HFU0IrUw==; Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7YmL-0005lI-TD; Mon, 17 Aug 2020 06:37:57 +0000 Date: Mon, 17 Aug 2020 07:37:57 +0100 From: Christoph Hellwig To: Leah Rumancik Cc: bpf@vger.kernel.org, linux-block@vger.kernel.org, orbekk@google.com, harshads@google.com, jasiu@google.com, saranyamohan@google.com, tytso@google.com, bvanassche@google.com Subject: Re: [RFC PATCH 0/4] block/bpf: add eBPF based block layer IO filtering Message-ID: <20200817063757.GA21966@infradead.org> References: <20200812163305.545447-1-leah.rumancik@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200812163305.545447-1-leah.rumancik@gmail.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Wed, Aug 12, 2020 at 04:33:01PM +0000, Leah Rumancik wrote: > This patch series adds support for a new security mechanism to filter IO > in the block layer. With this patch series, the policy for IO filtering > can be programmed into an eBPF program which gets attached to the struct > gendisk. The filter can either drop or allow IO requests. It cannot modify > requests. We do not support splitting of IOs, and we do not support > filtering of IOs that bypass submit_bio (such as SG_IO, NVMe passthrough). Which means it is not in any way useful for security, but just snake oil. But even if it wasn't this is a way to big hammer with impact for to the I/O fast path to be acceptable.