From patchwork Sun Sep 12 13:10:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Len Baker X-Patchwork-Id: 509691 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=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 63B14C433F5 for ; Sun, 12 Sep 2021 13:11:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4540B6108E for ; Sun, 12 Sep 2021 13:11:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235325AbhILNMw (ORCPT ); Sun, 12 Sep 2021 09:12:52 -0400 Received: from mout.gmx.net ([212.227.17.22]:35423 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235203AbhILNMv (ORCPT ); Sun, 12 Sep 2021 09:12:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1631452284; bh=A/5R/9lReRnqhX6VardHyEyyLao6a251fVotksIzRz4=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date; b=FHaHEneD/JHM91TlbiVBwG1FybHQieys3tZ581/oKQypH5ceh3JkG1LwdYEUL6OUw 6zj1G4LfYdl7CYUgq8mQYxfThp3P/JSkZuEBxw3M8hcg0ZHdfJBeXyg1egHrYH6464 boDX61NkPwYOm4kq+wa75mjkSLQzXO7r/gqNkrmw= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from localhost.localdomain ([79.150.72.99]) by mail.gmx.net (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1MbRfl-1mvz7q2KgT-00burL; Sun, 12 Sep 2021 15:11:23 +0200 From: Len Baker To: Simon Horman , Jakub Kicinski , "David S. Miller" Cc: Len Baker , Kees Cook , "Gustavo A. R. Silva" , oss-drivers@corigine.com, netdev@vger.kernel.org, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] nfp: Prefer struct_size over open coded arithmetic Date: Sun, 12 Sep 2021 15:10:57 +0200 Message-Id: <20210912131057.2285-1-len.baker@gmx.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Provags-ID: V03:K1:xQAYY+Wh3B5HSBfIXdY8+Kf81F3qLDBWMoLrHBOCyshSYw3i/RW e+K8wrfSv20BllJvs53spJa4W2SC/Mv0nkaEjszAWE1b1C0stbJ5yuK1Q0cUgoXk5rgjDaY aOWPEMQIO+qHqaiWI3sIAyDp+dapwOfvBkjnxxdNny1dTg/en3+bMDOcnLlL26N738cCTal 1d+67ZAZatc2kGXROTVOA== X-UI-Out-Filterresults: notjunk:1; V03:K0:u7CVJm1RPxk=:1VBoFGX8IlYt2jE+xxUaIL ff2UltfrQLU1mqqJb7jFf35QnbmQO57kMXAJy8gR22BDvBp/yUkhfmJ+8iNAeX194eyzWW2QD p8BHFY6AyLeKX425tsTzCJf99HV2pRGqpjzChBAM8aWbZ80YvAPdhkXLyqYjvin+TVNa0RjDE ux17lqoxq5O4wxeaXD25fqeNG8JLwCvZQKYyzx4tTOnyZy28q7hf0aZ/sUVL4xfRMiadE6RfK kRCqtMq78mOUWRcKl2fNVIPzEkLq1WPxBu9bfivYQThkGpmckjOgIkGt2JiYb1WDqgOca394K AL5rKMh+ynSQfq7+bd0lOWIu+TllD2tmDn9Jaz8ndQgyVbjVp1Ciphc9piPDWSqfpNDFB1+RM gHgfjNiNgbdd6qspL/UCMrn4t8NZtWUp/RvAk9BYgG0KLNgRuJB7jZkOZCxLFH1zANV+XnQPf M8yKSjH3ErFBF4peSaueVxXwil3/IxBLrBdzI+KZ81rxE5pQZukSOlAbWa6MTaOTokKXWyJ10 sItVP+HqXOXOYXIdP8A5l9srpgHUiGu6Dsi0f3fkv62PSvEyAlcTbOZqO3ZTssut97rUIpspu VG3IAxsuX2XfoeT82++CSkWAHIx6cbXK9fhz0VeQj9Q9kSSECoQZgwikkXiJ7T0bk7swReqyi AEbFRePf9c1/tN3oc5SC58riSmyIfEAQ1120E/muKiOAGTQ1ZNvtnixQAaO9P1vav/GLkU8/S PfWdhJDKK+Z1tv10ZFRT56wwpoc74oB3P4aJk+UKp+Few2Yfivok8fs3ChMiNNWvjE9IDR1Yz Z+R6IuayR0RKmkJAdahcBWc72e/V/E2jGj6OpLEqqPquvPeWM6t6JTwdBfv2Pbuju7KVamqP8 Btj0H2phmuaKntjKaww8TWdu6FsKttQCJCHDbbj4iYc6FRPtSEKOmarRtzB6DAIUBibdYB/NN +qQEjOPlqQdo4x/gfyLucU/3vTsoLi8yVPmf9s/bTJ64SoFzT4GG+HsOBd/u48GdPQfyfs3Tk N57YioDiW8zSvlaq7bLt5TpT3XxmwicI7pMS5pDFVi2NunBbW0AUSs9k2ve6mpwitKIYgCv8Y Rldt21TSBEQMd8= Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org As noted in the "Deprecated Interfaces, Language Features, Attributes, and Conventions" documentation [1], size calculations (especially multiplication) should not be performed in memory allocator (or similar) function arguments due to the risk of them overflowing. This could lead to values wrapping around and a smaller allocation being made than the caller was expecting. Using those allocations could lead to linear overflows of heap memory and other misbehaviors. So, use the struct_size() helper to do the arithmetic instead of the argument "size + count * size" in the kzalloc() function. [1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments Signed-off-by: Len Baker Reviewed-by: Gustavo A. R. Silva Reviewed-by: Simon Horman --- drivers/net/ethernet/netronome/nfp/nfp_net_repr.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) -- 2.25.1 diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_repr.c b/drivers/net/ethernet/netronome/nfp/nfp_net_repr.c index 3b8e675087de..369f6ae700c7 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_repr.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_repr.c @@ -499,8 +499,7 @@ struct nfp_reprs *nfp_reprs_alloc(unsigned int num_reprs) { struct nfp_reprs *reprs; - reprs = kzalloc(sizeof(*reprs) + - num_reprs * sizeof(struct net_device *), GFP_KERNEL); + reprs = kzalloc(struct_size(reprs, reprs, num_reprs), GFP_KERNEL); if (!reprs) return NULL; reprs->num_reprs = num_reprs;