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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9E2FAC05027 for ; Fri, 10 Feb 2023 16:59:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232514AbjBJQ7K (ORCPT ); Fri, 10 Feb 2023 11:59:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40486 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232178AbjBJQ7A (ORCPT ); Fri, 10 Feb 2023 11:59:00 -0500 Received: from mail-io1-xd30.google.com (mail-io1-xd30.google.com [IPv6:2607:f8b0:4864:20::d30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D8E51A674 for ; Fri, 10 Feb 2023 08:58:57 -0800 (PST) Received: by mail-io1-xd30.google.com with SMTP id 65so2169903iou.3 for ; Fri, 10 Feb 2023 08:58:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; t=1676048337; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=rrh0NDaHMY9O1FS98P5dAqfFDyWSfS3HhhQqFVWgZOE=; b=DVL3MPv9sMruszS7zHhzndY8WHnB6AgksAFy5dqTvW8M30CClTuuVf7NpuIbfmxU5w pN7Fts0Q/8DEk6TyOdtTCW4+EpLxQaOevBd6wEBwPAZ6TPnO9UJRRzOccQdfWsKsbpGf +Uehyf0N1dlc4Blds753OkcWDZ3c/iD+XNlkfleSsbRxKHHW2C9QuU2aNlX/ONLmJw8D JZrd0x3iPYjK8QVCTdAG0sD90OVMnT7o0c+goUq2LBJFyZb0zCbZObrmtPI5cxs8bWch S8uWwqv20BE9dH94mf/tMTQ2rWldZ5CguUhUvlW8l5FYXszzB7P0+zRz/qOcaKsIz8AG 1BIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1676048337; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=rrh0NDaHMY9O1FS98P5dAqfFDyWSfS3HhhQqFVWgZOE=; b=wsXjC2+hCdwzYntiCkI4FmmWib/KUAhuMIrT7kkBmo0HST7QSh8FUBxNSR401T8S7J bkDHMSBA2nk7zABx615W9A6GN+yRteCShTFYLijfVXdBWtU8s7rPDJCMQRiQfnMUKafD hAIBySRjCghs3ivwxOsOqKq6plZwJVFNE+v2J19UIsW8FbFEK1N0rsVQzsSnyGafrDIu kzmUWlX6jnBcW31ngeqB8Fr1visUNhu9wcthuDjoOdzIQBtwgPdgXe+9y/2yp5c3JhRp LRXyKRkYEYGzUEZB50Dh2AqgN4Wl1NXx9NB2iaCCZSl/1Z4EG+mttQ/JB8AiqeJzYbH0 q6uA== X-Gm-Message-State: AO0yUKXG2+tn7NK3dy6/l5yc39ecOXjPm5QuUiQIaVJThsEAZU33HRsW rCWb61fmo1je+6d5qg9JF8CJUA== X-Google-Smtp-Source: AK7set/CyHbofIp/G2RL2FgjvDqyudxHU+KGsBOzNuN7iKexvugyLUIJFiToFdDTBQJyRSyu93edbg== X-Received: by 2002:a6b:7019:0:b0:72c:f57a:a37b with SMTP id l25-20020a6b7019000000b0072cf57aa37bmr10159969ioc.2.1676048336820; Fri, 10 Feb 2023 08:58:56 -0800 (PST) Received: from [192.168.1.94] ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id f4-20020a02a804000000b003aabed37b1bsm1499059jaj.175.2023.02.10.08.58.55 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 10 Feb 2023 08:58:56 -0800 (PST) Message-ID: <6340bd43-c96e-9702-e00a-b426f05b0271@kernel.dk> Date: Fri, 10 Feb 2023 09:58:55 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: [PATCH v2] io_uring,audit: don't log IORING_OP_MADVISE Content-Language: en-US To: Paul Moore Cc: Steve Grubb , Richard Guy Briggs , LKML , io-uring@vger.kernel.org, Eric Paris , Christian Brauner , Stefan Roesch References: <13293926.uLZWGnKmhe@x2> <6939adfb-ce2c-1911-19ee-af32f7d9a5ca@kernel.dk> <56ef99e4-f9de-0634-ce53-3bc2f1fa6665@kernel.dk> From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 2/10/23 9:52?AM, Paul Moore wrote: > On Fri, Feb 10, 2023 at 11:00 AM Jens Axboe wrote: >> On 2/10/23 8:39?AM, Paul Moore wrote: >>> On Thu, Feb 9, 2023 at 7:15 PM Jens Axboe wrote: >>>> On 2/9/23 3:54?PM, Steve Grubb wrote: >>>>> On Thursday, February 9, 2023 5:37:22 PM EST Paul Moore wrote: >>>>>> On Thu, Feb 9, 2023 at 4:53 PM Richard Guy Briggs wrote: >>>>>>> On 2023-02-01 16:18, Paul Moore wrote: >>>>>>>> On Wed, Feb 1, 2023 at 3:34 PM Richard Guy Briggs >>>>> wrote: >>>>>>>>> fadvise and madvise both provide hints for caching or access pattern >>>>>>>>> for file and memory respectively. Skip them. >>>>>>>> >>>>>>>> You forgot to update the first sentence in the commit description :/ >>>>>>> >>>>>>> I didn't forget. I updated that sentence to reflect the fact that the >>>>>>> two should be treated similarly rather than differently. >>>>>> >>>>>> Ooookay. Can we at least agree that the commit description should be >>>>>> rephrased to make it clear that the patch only adjusts madvise? Right >>>>>> now I read the commit description and it sounds like you are adjusting >>>>>> the behavior for both fadvise and madvise in this patch, which is not >>>>>> true. >>>>>> >>>>>>>> I'm still looking for some type of statement that you've done some >>>>>>>> homework on the IORING_OP_MADVISE case to ensure that it doesn't end >>>>>>>> up calling into the LSM, see my previous emails on this. I need more >>>>>>>> than "Steve told me to do this". >>>>>>>> >>>>>>>> I basically just want to see that some care and thought has gone into >>>>>>>> this patch to verify it is correct and good. >>>>>>> >>>>>>> Steve suggested I look into a number of iouring ops. I looked at the >>>>>>> description code and agreed that it wasn't necessary to audit madvise. >>>>>>> The rationale for fadvise was detemined to have been conflated with >>>>>>> fallocate and subsequently dropped. Steve also suggested a number of >>>>>>> others and after investigation I decided that their current state was >>>>>>> correct. *getxattr you've advised against, so it was dropped. It >>>>>>> appears fewer modifications were necessary than originally suspected. >>>>>> >>>>>> My concern is that three of the four changes you initially proposed >>>>>> were rejected, which gives me pause about the fourth. You mention >>>>>> that based on your reading of madvise's description you feel auditing >>>>>> isn't necessary - and you may be right - but based on our experience >>>>>> so far with this patchset I would like to hear that you have properly >>>>>> investigated all of the madvise code paths, and I would like that in >>>>>> the commit description. >>>>> >>>>> I think you're being unnecessarily hard on this. Yes, the commit message >>>>> might be touched up. But madvise is advisory in nature. It is not security >>>>> relevant. And a grep through the security directory doesn't turn up any >>>>> hooks. >>>> >>>> Agree, it's getting a bit anal... FWIW, patch looks fine to me. >>> >>> Call it whatever you want, but the details are often important at this >>> level of code, and when I see a patch author pushing back on verifying >>> that their patch is correct it makes me very skeptical. >> >> Maybe it isn't intended, but the replies have generally had a pretty >> condescending tone to them. That's not the best way to engage folks, and >> may very well be why people just kind of give up on it. Nobody likes >> debating one-liners forever, particularly not if it isn't inviting. > > I appreciate that you are coming from a different space, but I stand > by my comments. Of course you are welcome to your own opinion, but I > would encourage you to spend some time reading the audit mail archives > going back a few years before you make comments like the above ... or > not, that's your call; I recognize it is usually easier to criticize. I'm just saying how it was received on my end, you can take that as constructive feedback or ignore it. I don't need to read the archives for that as it is not related to anything but this thread, it was not meant to reflect a general concern outside of this thread. > On a quasi related note to the list/archives: unfortunately there was > continued resistance to opening up the linux-audit list so I've setup > audit@vger for upstream audit kernel work moving forward. The list > address in MAINTAINERS will get updated during the next merge window > so hopefully some of the problems you had in the beginning of this > discussion will be better in the future. OK good, I keep forgetting to delete it from the replies and get annoyed at the spam I get back... Thanks for fixing that going forward. >>> I really would have preferred that you held off from merging this >>> until this was resolved and ACK'd ... oh well. >> >> It's still top of tree. If you want to ack it, let me know and I'll add >> it. If you want to nak it, give me something concrete to work off of. > > I can't in good conscience ACK it without some comment from Richard > that he has traced the code paths; this shouldn't be surprising at > this point. I'm not going to NACK it or post a revert, I would have > done that already if I felt that was appropriate. Right now this > patch is in a gray area for me in that I suspect it is good, but I > can't ACK it without some comment that it has been properly > researched. Richard, can you do the due diligence here? Steve did say: "But madvise is advisory in nature. It is not security relevant. And a grep through the security directory doesn't turn up any hooks." Seems to me if we're not currently auditing madvise outside of io_uring, then why would we do it here? -- Jens Axboe