From patchwork Sat Sep 11 11:26:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Len Baker X-Patchwork-Id: 12537675 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,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 263CDC433F5 for ; Sat, 11 Sep 2021 11:26:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 08FA5610C8 for ; Sat, 11 Sep 2021 11:26:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231749AbhIKL2C (ORCPT ); Sat, 11 Sep 2021 07:28:02 -0400 Received: from mout.gmx.net ([212.227.17.20]:57281 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230249AbhIKL2C (ORCPT ); Sat, 11 Sep 2021 07:28:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1631359607; bh=G8MUuBpNtnBNxQFmEG2ZlriHlD7R4/yuBbjO5Ngy/bk=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date; b=J7+O/q5h+I2kZg3xNyRxgirD/9jSmAllZs6+S9q5aabZCbMLWPbDy/1smQhpOOFa5 LMamsWd5C5hj9F6PdbGIzFK+0RkEyuCkpqIhX3ZhgEm3+YnCaXz45KHbdXa/9PtCA+ k4wdX/bSl48iiBmCa4vyAAi25ZS3ApiifahMAf9w= 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 1My32F-1n8rk1313v-00zVbD; Sat, 11 Sep 2021 13:26:46 +0200 From: Len Baker To: Alan Stern , Greg Kroah-Hartman Cc: Len Baker , Kees Cook , linux-usb@vger.kernel.org, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] usb: ohci: Prefer struct_size over open coded arithmetic Date: Sat, 11 Sep 2021 13:26:31 +0200 Message-Id: <20210911112631.10004-1-len.baker@gmx.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Provags-ID: V03:K1:SOgd2+Qv+9I1QBgs75UshmVAAaFWc90Wg57FZNwfUUC6f8n5T8f HJw96UmmQebgnfQYnnxxmXbKH1HcO8USYLODFrtqDgXlMR0vo7F6Titc4F19OUwwSQPMeBG dfHe718u1e2BtEmh0rIxyDCq8ihyGbm6nIxKQYaaO3zjNkmBLJaDVgt7Jq/BhWEIvmRLZnW IGGqhk3VDeYtW3tXO2eNA== X-UI-Out-Filterresults: notjunk:1;V03:K0:8h8+1ruWDmA=:554Ej/I6jXV1JUfMIWrw5J ake8jIw9w82IDeMl5cfWTP/XtoPS/DNg6V/FfRMlO/T87lQ1sbmSlPdXqCHzseAXJdJqOK1Wk 1nWtgh7ZScL+XUy8ePANoIx2YFoaRTVvy02zEgvutD8e191gWOqC+tf2ShBvgGUxwjYonOio8 wKhdqLdmHrPgMoC6ILHH9GeUcJyagc7+jTWjJq6f7zXNhNTCvoq5Mg4FXQeNBwjDEPwXrWvJV ynu6nAWULXw4+IUbwB9UuIpWWtukRCCiAx3x/YFHqta5GYvff3eAO37hEAHzqY06Hfk2LKmL7 lahEv5Jhf4MCAfhO5WhD2L6W6lsVSuAMYzUb0H7QKwMciskhNVuUMTUuFckvzbnkO1F+dNVzO L6eP2aowal7nkAJFb/M3Cp9gbNNOG2kzLZVT8Fc+Ezj1C+A9lGklfWJEE2IsLAH45+vTdoNWM MeXaWDLWBwYqxhrGWKc1L52tHsrDWdTcGQbHIUPeQ8k2T9o+iNGYXynEF+fK6GoaZ0WPwdV32 uavPGGoxnbAkyMYt52CLXbDPY0HWZXXj/+6s4weE54QrRvk33GPGj8kSvp2BMPVSFv9ZvIpoJ 5nRO64TS4brSQuqZvoguBKbH6LbniTZDGt94A29iSEqINR4mTNxnUPJhWVvecsvpwuQ1f5RvP FkstAC/yBkuJxS731Y7U0oWRMOYRhdUUc5B8BU4SH+Wh+qhHOzgynqLMu4sMDV5ZCQhTkgy36 z64Wyh1h9JXu6+eH/OXVAYyaWKesEUvTNG7p00B5qz9q90a/c/e0hQXFM8cBEzxqzNKidisAt 1Mz2bo4OgEnJvtqTPNBLHiGSbMWk7QoV1fUk75ALnfjX8Wlb+S+/OaejTAafFiqEkI4htq+iR FPEaJHYvCVUQVVLnE19KGftux1zL7XHxE+I0iAziMPs49BoeOSm461ysNhiPjWo3U4RwtTM0X Km3oeuJ3tl1POnBt3fmq8/s1TWmkTu520VEGooSYAoarrXQ3hsBarkj2b7KnnWl8Y9X8nxU2K Ieqz1ew2T8uFO/rZLUn2CYMmQflqpxMoimpHo682UKYm1M1U7TQZ1HML9DA8lgSZgKANy5ZRM a7VcIcymeOjO20= Precedence: bulk List-ID: X-Mailing-List: linux-hardening@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 Acked-by: Alan Stern --- drivers/usb/host/ohci-hcd.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) -- 2.25.1 diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c index 1f5e69314a17..666b1c665188 100644 --- a/drivers/usb/host/ohci-hcd.c +++ b/drivers/usb/host/ohci-hcd.c @@ -191,8 +191,7 @@ static int ohci_urb_enqueue ( } /* allocate the private part of the URB */ - urb_priv = kzalloc (sizeof (urb_priv_t) + size * sizeof (struct td *), - mem_flags); + urb_priv = kzalloc(struct_size(urb_priv, td, size), mem_flags); if (!urb_priv) return -ENOMEM; INIT_LIST_HEAD (&urb_priv->pending);