From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932785AbeCLP6u (ORCPT ); Mon, 12 Mar 2018 11:58:50 -0400 Received: from mailout4.samsung.com ([203.254.224.34]:11613 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932582AbeCLP6s (ORCPT ); Mon, 12 Mar 2018 11:58:48 -0400 DKIM-Filter: OpenDKIM Filter v2.11.0 mailout4.samsung.com 20180312155846epoutp0453288b886cc316f87f43a1fbc5c30c01~bN4D8CF2q1388113881epoutp04l X-AuditID: b6c32a47-19fff7000000100c-37-5aa6a3b544be From: Bartlomiej Zolnierkiewicz To: "Gustavo A. R. Silva" Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: Re: [PATCH] video: fbdev: vermilion: use 64-bit arithmetic instead of 32-bit Date: Mon, 12 Mar 2018 16:58:38 +0100 Message-id: <3883400.1vCYa0i6ig@amdc3058> User-Agent: KMail/4.13.3 (Linux/3.13.0-96-generic; KDE/4.13.3; x86_64; ; ) In-reply-to: <20180207000424.GA32680@embeddedgus> MIME-version: 1.0 Content-transfer-encoding: 7Bit Content-type: text/plain; charset="us-ascii" X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrCIsWRmVeSWpSXmKPExsWy7bCmme62xcuiDGanW1z5+p7NYuWS/WwW W/eoWpzo+8BqcXnXHDYHVo91B1U97ncfZ/L4vEkugDmKyyYlNSezLLVI3y6BK2P1igOMBR/Y Kr5/PMrawHiKtYuRk0NCwETiyd1TbF2MXBxCAjsYJf52r2WGcL4zSjStaAWq4gCr6vquDBHf wCgxfXUXC0i3kMBXRol1i+NAbDYBK4mJ7asYQWwRASOJ2TO6WUEamAUmM0q0b1vLBJIQFgiX uHBvO5jNIqAqsXEdiM3BwSugKfFtthVIWFTAS2LLvnawEk4BQ4mJ91eB2bwCghI/Jt8D28ss IC+xb/9UVghbR+LssXWMILskBJawSazeNY0N4jUXiSmXvjBC2MISr45vYYewpSWerdoI1dDM KPFtxx5miMQERok964UgbGuJw8cvQm3gk+g4/JcdEhK8Eh1tUCUeEpv+vIdqdZRo3PWFERJC LYwSN9t3sk9glJ2F5PBZSA6fheTwBYzMqxjFUguKc9NTi40KjPWKE3OLS/PS9ZLzczcxguNe y30H47ZzPocYBTgYlXh4DZqXRQmxJpYVV+YeYpTgYFYS4fWfChTiTUmsrEotyo8vKs1JLT7E KM3BoiTO2xrgEiUkkJ5YkpqdmlqQWgSTZeLglGpgTPzf2May/MIEIwe5jWr1l7fqztOs/aKc 0MdiZudQGczsO90hUfKSv1uv1I5Lzmy/U3/f9Nw8SVuEsySgt8j79fJnDAePOdrvfx257qF8 n8ibRLczX/b67fuuySyxrq92/53CgsxF+n+Nhf/NvchfN3tNsUuZv+O2jwl9b/61z2U8/3Xx 1Bu3lFiKMxINtZiLihMB0b5ZLvcCAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrHLMWRmVeSWpSXmKPExsVy+t9jQd2ti5dFGey8yWNx5et7NouVS/az WWzdo2pxou8Dq8XlXXPYHFg91h1U9bjffZzJ4/MmuQDmKC6blNSczLLUIn27BK6M1SsOMBZ8 YKv4/vEoawPjKdYuRg4OCQETia7vyl2MXBxCAusYJY68v8IG4XxllDj5o4uli5GTg03ASmJi +ypGEFtEwEhi9oxuVpAiZoGJjBJ3p7xlBkkIC4RLrPw6iwnEZhFQldi4bjsTyAZeAU2Jb7Ot QMKiAl4SW/a1g5VwChhKTLy/igliWRujxIq5O9hAErwCghI/Jt8DW8wsIC+xb/9UVghbS2L9 zuNMExj5ZyEpm4WkbBaSsgWMzKsYJVMLinPTc4uNCozyUsv1ihNzi0vz0vWS83M3MQJDddth rf4djI+XxB9iFOBgVOLh7WhdFiXEmlhWXJl7iFGCg1lJhNd/KlCINyWxsiq1KD++qDQntfgQ ozQHi5I4L3/+sUghgfTEktTs1NSC1CKYLBMHp1QDo2/0WqaHUUXv/32V1Ilrkd6rdqMnmiM1 SyVd48XVg508O0wVJ/YdtPq/dvG8Tj2t85ZPgmfp7jCvCxZcJTs7dnaaS9IZw6Jc96Pe/ete 61p9uOp+3ObWH7+9+/hmlojNELcsY746ocErQaR9UeRUr7IDdle7j18Qjr6z70TejhsHkpvn bKq7pcRSnJFoqMVcVJwIAENz+PlRAgAA X-CMS-MailID: 20180312155845epcas2p45ac49e920a8b708fcd5d8244a658857a X-Msg-Generator: CA CMS-TYPE: 102P X-CMS-RootMailID: 20180207000429epcas3p49ce7f7528d02b9799713e8806d77847d X-RootMTR: 20180207000429epcas3p49ce7f7528d02b9799713e8806d77847d References: <20180207000424.GA32680@embeddedgus> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday, February 06, 2018 06:04:24 PM Gustavo A. R. Silva wrote: > Cast _pitch_ to u64 in order to give the compiler complete information > about the proper arithmetic to use. Notice that this variable is > being used in a context that expects an expression of type u64 > (64 bits, unsigned). > > The expression pitch * var->yres_virtual is currently being evaluated > using 32-bit arithmetic and the result of the operation is being stored > into variable mem, which is a variable of type u64. Based on that, > chances are there is a potential integer overflow as a result of the > operation. > > Addresses-Coverity-ID: 200655 ("Unintentional integer overflow") > Signed-off-by: Gustavo A. R. Silva Patch queued for 4.17, thanks. Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics