From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Date: Fri, 25 Oct 2019 12:54:55 +0000 Subject: Re: [PATCH][next] io-wq: fix unintentional integer overflow on left shift Message-Id: List-Id: References: <20191025124315.21742-1-colin.king@canonical.com> In-Reply-To: <20191025124315.21742-1-colin.king@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Colin King , Alexander Viro , linux-fsdevel@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org On 10/25/19 6:43 AM, Colin King wrote: > From: Colin Ian King > > Shifting the integer value 1U is evaluated with type unsigned int > using 32-bit arithmetic and then used in an expression that expects > a 64-bit value, so there is potentially an integer overflow. Fix this > by using the BIT_ULL macro to perform the shift and avoid the overflow. Good catch, that should indeed have been 1ULL. I'll fold in your fix, thanks! -- Jens Axboe 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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 1DC12CA9EA0 for ; Fri, 25 Oct 2019 12:54:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E0FE521929 for ; Fri, 25 Oct 2019 12:54:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="FGzHDnk9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2504638AbfJYMy6 (ORCPT ); Fri, 25 Oct 2019 08:54:58 -0400 Received: from mail-io1-f67.google.com ([209.85.166.67]:45968 "EHLO mail-io1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2504636AbfJYMy6 (ORCPT ); Fri, 25 Oct 2019 08:54:58 -0400 Received: by mail-io1-f67.google.com with SMTP id c25so2240926iot.12 for ; Fri, 25 Oct 2019 05:54:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=XqRZL3LD0cAYpu4i+Oz5gNumeaGbwkRBXuU0UymszRw=; b=FGzHDnk90eDcHEqQWBtHbS3AqS9XkVlgVqg8Fd/yZObK1UxjtNbnkzE5l1zepmuPRt cyes7m2M8EpWs9YBTaEhM3KTiF1PGqCHVc4Y1WdjrYQNQouiqoOWPD5QQEhHWWpgVZz/ e856QHAOTtBAoIyYul0s8yv+7tN+FJp0X4oepfLB7PK7iDZL2UUgnbZ5tJoFy2ffytTo lezWPU0QbbjY0zNb46QXfJ3CReBKOH3x9+6QQL6wgMrGLESuaSMJty1UuYhYP/Pqtpn3 O9gnBqnzoG6ynfXyoP3XcHbGsbbf6hE9kU9/tNabsHlTWiv5RxCN8icaVFOTafceI+cG ztSQ== 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=XqRZL3LD0cAYpu4i+Oz5gNumeaGbwkRBXuU0UymszRw=; b=qOIDfvmmJKbhaByqTeLTMl2FfHvbKvVr28IO8Si8VYEmkolz7AgsOXZOtwoZaNPbDS 9YxEaCRhQ2oYW+u97VsPFDTXvbOJUPcxHTiViRaTXlJ+2bERYm0fwpvUaVjGMkpnL4gJ qxtyYypDlM2RvErbmrD96+tCiPzQCLDYK4j0UwJhb1t5DxafvAYw9zl3W1V3qEXycail qNkgL80kDlA/0XO+iPB//c85wBJAKT8RKp6FCZfD7rcdHCGqseLXcnia2CAKJ1/HzNq6 9g5Ilk4ucZtbX0XieV1j0M/YjIWiU+LedJRj+2GNkxgLniRd7pgF455f1RdgsLppDzEs eEFA== X-Gm-Message-State: APjAAAWy0l+EVWanjwD+Hg6at1PVjSatNbCA7X97hqcEEtnpO/I0XRN5 rHHiL4VGmGS6wGmOAh8v73YY3g== X-Google-Smtp-Source: APXvYqyRv6QNh4wAE0Yq4PNSmeWazYkJpqCtu/Gt2kSofhSOTEiA6Gjj45It1k+vN2/LmYqGl4akaw== X-Received: by 2002:a6b:f415:: with SMTP id i21mr3597034iog.109.1572008097263; Fri, 25 Oct 2019 05:54:57 -0700 (PDT) Received: from [192.168.1.159] ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id l64sm66767ilh.2.2019.10.25.05.54.55 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 25 Oct 2019 05:54:56 -0700 (PDT) Subject: Re: [PATCH][next] io-wq: fix unintentional integer overflow on left shift To: Colin King , Alexander Viro , linux-fsdevel@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org References: <20191025124315.21742-1-colin.king@canonical.com> From: Jens Axboe Message-ID: Date: Fri, 25 Oct 2019 06:54:55 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20191025124315.21742-1-colin.king@canonical.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 10/25/19 6:43 AM, Colin King wrote: > From: Colin Ian King > > Shifting the integer value 1U is evaluated with type unsigned int > using 32-bit arithmetic and then used in an expression that expects > a 64-bit value, so there is potentially an integer overflow. Fix this > by using the BIT_ULL macro to perform the shift and avoid the overflow. Good catch, that should indeed have been 1ULL. I'll fold in your fix, thanks! -- Jens Axboe