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 67F84C433FE for ; Wed, 6 Apr 2022 15:38:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235937AbiDFPkf (ORCPT ); Wed, 6 Apr 2022 11:40:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236042AbiDFPj5 (ORCPT ); Wed, 6 Apr 2022 11:39:57 -0400 Received: from mail-pg1-x52c.google.com (mail-pg1-x52c.google.com [IPv6:2607:f8b0:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C78EF1B72FE for ; Wed, 6 Apr 2022 05:55:34 -0700 (PDT) Received: by mail-pg1-x52c.google.com with SMTP id 125so2105440pgc.11 for ; Wed, 06 Apr 2022 05:55:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=Ia9+/STEIK6s5M7yq5g28XApY0uGE7BS8OCfCM69b6A=; b=1jHJjG0vgz25gIzyBuScalLuzhFAfWyPNeNxdThD5QdRv6nV6NS/H9b5sgMPyXcpeA jCApD1jmvsgeKI5/tguxrCXmMwlkeU+UtDeN87DbXpH4BDnpcB6dNPoaNFysouTNi34D mwPOhoX8zj1JT2o34AsxHa7g1kWrXlKyqZo4B12OymnG/M27MMOZOiT0ZqBIcj9nC5R8 nEgHt4nRlVA9IBDe+fKF7fgMLJMJoAxtikpXI44H+hEZOFb1kQS4ccI3urifRwJofOu2 YNBnw7a4es5sxt9ZeJGKY6WGELxoWRLrYJlPP0GAzQkQbAbpFKYrApa4HUSOepOQTWEw CfNQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=Ia9+/STEIK6s5M7yq5g28XApY0uGE7BS8OCfCM69b6A=; b=qVdUDTjBbmyRHpzPX4lJZvucT2eFcO6QsJAudRCSosrDRYmtzbKBPuWTwMeraKgmqh Phh9qSj/Z+c3BeoAY52b+LNwBFTlJH4mqOlfyfhdRfwFzgBnxvwj8C+aezDAwOP4WUPt XLMijvwiTrQ6k81LoOq0OJjoOd6c2akgwbR55LX8SyxQiUzzBvB/Deh5vuuKTfzi4Enq 6UmUpMrw0pz8ANwuHF5w4TAyZlHa0kNp5j/o6Pcy97IDBpmfZXLnDMjyy+/TH82mQcDj GpcWbrqGGhTijgQBg/uCn/6yER1mIvMgoAIpWJ6cT/Q+XH7tuaEQu9MoVofaze9Xwa4e SkEQ== X-Gm-Message-State: AOAM530qoY9tQNfmBDfcxk8P1a7ZBB3QJso8lnUhpLCfHcfvRssHqxCh oVgU3tMhNrvaH4u295d/rlmsDA== X-Google-Smtp-Source: ABdhPJw2Mh1njoqbEPjpvRC2p3sOjeTsg/pWyOftIQWGeQ7ifA9CMlk2Fr9+xIAJq2EzH3psDacsUg== X-Received: by 2002:a05:6a00:a92:b0:4e0:57a7:2d5d with SMTP id b18-20020a056a000a9200b004e057a72d5dmr8534617pfl.81.1649249734194; Wed, 06 Apr 2022 05:55:34 -0700 (PDT) Received: from [192.168.1.100] ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id a38-20020a056a001d2600b004f72acd4dadsm19647671pfx.81.2022.04.06.05.55.33 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 06 Apr 2022 05:55:33 -0700 (PDT) Message-ID: <263199dd-34e4-36ff-51ef-23a8f4bbe5b2@kernel.dk> Date: Wed, 6 Apr 2022 06:55:32 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH -next] nbd: fix possible overflow on 'first_minor' in nbd_dev_add() Content-Language: en-US To: Zhang Wensheng , josef@toxicpanda.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, nbd@other.debian.org References: <20220406112449.2203191-1-zhangwensheng5@huawei.com> From: Jens Axboe In-Reply-To: <20220406112449.2203191-1-zhangwensheng5@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/6/22 5:24 AM, Zhang Wensheng wrote: > When 'index' is a big numbers, it may become negative which forced > to 'int'. then 'index << part_shift' might overflow to a positive > value that is not greater than '0xfffff', then sysfs might complains > about duplicate creation. Because of this, move the 'index' judgment > to the front will fix it and be better. What's changed in this version? Always add a v2 to both the subject line and below the '---' so that folks reviewing this will know what changes you made since the last posting. -- Jens Axboe