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=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 646C6C2D0DB for ; Wed, 29 Jan 2020 14:34:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 367C220732 for ; Wed, 29 Jan 2020 14:34:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="bKyaTHP5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726261AbgA2Oe0 (ORCPT ); Wed, 29 Jan 2020 09:34:26 -0500 Received: from mail-lf1-f49.google.com ([209.85.167.49]:43642 "EHLO mail-lf1-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726178AbgA2OeZ (ORCPT ); Wed, 29 Jan 2020 09:34:25 -0500 Received: by mail-lf1-f49.google.com with SMTP id 9so12013780lfq.10; Wed, 29 Jan 2020 06:34:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=Dqjs3MSryJQ2/G+YDTPrCLSOlbtWyQ155CnzyE2MZAY=; b=bKyaTHP5K5jrgKdsp7LLDH9jGaUhbmgdRF5EStAZWoG5JCiuKk4Nh5YNQkOs0bG5P0 xKlJLisXUysF5fhDLoYCUI06PtSA9D4Qz9JzoLbklLq7/Ge8kiXv6WHI4JR8KyPkVRgX AASGJ23YBLH1rffGXm3BUOErwVYJTshPPimJbsyTMj1KCiYWbu67OsGpc1vb/yns64IQ XVwA0VTeqbz9BjEslDVoJEuqFnAqMiUb0Ut5Rpokvr7XFpoAwNb47Iv2D41PZcI+fvO/ GA6L/horcup4m1680IuJKBefktPXmUb5RvOSVrrWFL31swLh1VPXDigh05S2qKYDmLvK c8ow== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Dqjs3MSryJQ2/G+YDTPrCLSOlbtWyQ155CnzyE2MZAY=; b=OnjXvr2R3JY3VxQ00+7CjC4SOeFDOwegJska0UN5ahD0CrZBFAZO51xHTSfdM9PXfY i3N0b29RQGOWOexgCYe1eDPDcKnuhEyOXIMSugWzOoGXIESnT9jxSW9mIuH4wRA7z20w iLZil6iMCRNb8rwxGm3Fh6gaD4CNm0PbgzXsp9p/g6GdJkqPP+qV8i47i+C7Wlb3d+MB Rvfx0yF39fcdBn2q52uKCxgAj41GmIm8wIQSnHXpdHClJCLNFeTv6Emhr/tiYIe5fPiK cPTSLf6pZo1BcvWr39SLnVbdNMwpZKo4ahAAQvnscH3dvhTIXxDghHckGHY7fdFhBnqQ UM/w== X-Gm-Message-State: APjAAAWJbOOEEt6yYwZ1m2qYWS25Oz9tVat/W4Vqa5vor9Yw03vec1pe BI/O8Hbpc4WvE2tvUHMqLQqdRLPLeuc= X-Google-Smtp-Source: APXvYqxOjB3FHd6P4jFukao9ORSnX799m625sGeI0zqFjMZUEqvAH3IjVlaNuUTzA1ox4JuVQrifTw== X-Received: by 2002:ac2:5a48:: with SMTP id r8mr5871829lfn.179.1580308462964; Wed, 29 Jan 2020 06:34:22 -0800 (PST) Received: from [172.31.190.83] ([86.57.146.226]) by smtp.gmail.com with ESMTPSA id d26sm1177418lfa.44.2020.01.29.06.34.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 29 Jan 2020 06:34:22 -0800 (PST) Subject: Re: IORING_REGISTER_CREDS[_UPDATE]() and credfd_create()? To: Stefan Metzmacher , Jens Axboe Cc: io-uring , Linux API Mailing List References: <688e187a-75dd-89d9-921c-67de228605ce@samba.org> <1ac31828-e915-6180-cdb4-36685442ea75@kernel.dk> <0d4f43d8-a0c4-920b-5b8f-127c1c5a3fad@kernel.dk> <2d7e7fa2-e725-8beb-90b9-6476d48bdb33@gmail.com> <6c401e23-de7c-1fc1-4122-33d53fcf9700@kernel.dk> <35eebae7-76dd-52ee-58b2-4f9e85caee40@kernel.dk> <6e5ab6bf-6ff1-14df-1988-a80a7c6c9294@gmail.com> <2019e952-df2a-6b57-3571-73c525c5ba1a@kernel.dk> <0df4904f-780b-5d5f-8700-41df47a1b470@kernel.dk> <5406612e-299d-9d6e-96fc-c962eb93887f@gmail.com> <821243e7-b470-ad7a-c1a5-535bee58e76d@samba.org> <9a419bc5-4445-318d-87aa-1474b49266dd@gmail.com> <40d52623-5f9c-d804-cdeb-b7da6b13cb4f@samba.org> <3e1289de-8d8e-49cf-cc9f-fb7bc67f35d5@gmail.com> <6ebe1e2f-77f4-ae88-e184-c140a911cbd8@samba.org> From: Pavel Begunkov Message-ID: <1f7cafc5-1969-1c6d-6fb1-441854d60fcb@gmail.com> Date: Wed, 29 Jan 2020 17:34:21 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <6ebe1e2f-77f4-ae88-e184-c140a911cbd8@samba.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 1/29/2020 5:27 PM, Stefan Metzmacher wrote: >> Great, that you turned attention to that! override_creds() is already >> grabbing a ref, so it shouldn't call get_cred() there. >> So, that's a bug. >> >> It could be I'm wrong with the statement above, need to recheck all this >> code to be sure. >> >> BTW, io_req_defer_prep() may be called twice for a req, so you will >> reassign it without putting a ref. It's safer to leave NULL checks. At >> least, until I've done reworking and fixing preparation paths. > > Ok, but that would be already a bug in > "io_uring/io-wq: don't use static creds/mm assignments" > instead of logically being part of > "io_uring: support using a registered personality for commands" Right. Probably should be backported there, since it's just 2 commits before. -- Pavel Begunkov