From patchwork Tue Jan 11 07:55:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 12709581 X-Patchwork-Delegate: gustavo@embeddedor.com 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 8FB62C433F5 for ; Tue, 11 Jan 2022 07:48:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348651AbiAKHsv (ORCPT ); Tue, 11 Jan 2022 02:48:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235691AbiAKHsu (ORCPT ); Tue, 11 Jan 2022 02:48:50 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8EAA6C06173F; Mon, 10 Jan 2022 23:48:50 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 4BADEB81616; Tue, 11 Jan 2022 07:48:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F3CABC36AE9; Tue, 11 Jan 2022 07:48:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1641887328; bh=9JOkw+VWeYPNxcZNuDRsaZ8ozRwtIHSZxm6gsaTaUyI=; h=Date:From:To:Cc:Subject:From; b=TNhvLTHpyAAJ3FnB3MXuQ//gM8c7OGEdO7A+CY2p73E14yUWFwNWAZlkq6+jyX7v4 ZVG5rxR3LjTDnrqn1zbTHqCkeckZJhnMPsfvZ0iRPUVqYT8hKXCU+FRPl2xQ6JQWj+ P1g72VEsjI2gShpXVyZbxW8Yekk7u0gU2m3c/OedeEUXcyqJeEd6NRtND6Fzo78vXi pu6IhJ2LJO+yVyi8Ip9Jgvwh2vOqhTqut+59fROvHi8bOA1aj7EkEG4KZfE+k2Rn/9 mIoGVgoFhuMTE54icuSnZqCDnFXtNRGP/SCWhnHMuf6rGHVpB/IkwowJsNplXsL9Lx /Jh4SDlZBjr+Q== Date: Tue, 11 Jan 2022 01:55:13 -0600 From: "Gustavo A. R. Silva" To: Minas Harutyunyan , Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" , linux-hardening@vger.kernel.org Subject: [PATCH][next] usb: dwc2: Use flex_array_size() helper Message-ID: <20220111075513.GA76424@embeddedor> MIME-Version: 1.0 Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org Make use of the flex_array_size() helper to calculate the size of a flexible array member within an enclosing structure. This helper offers defense-in-depth against potential integer overflows, while at the same time makes it explicitly clear that we are dealing with a flexible array member. Link: https://github.com/KSPP/linux/issues/160 Signed-off-by: Gustavo A. R. Silva --- drivers/usb/dwc2/hcd.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index f63a27d11fac..2c21498662cd 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -4054,8 +4054,9 @@ struct dwc2_tt *dwc2_host_get_tt_info(struct dwc2_hsotg *hsotg, void *context, * For single_tt we need one schedule. For multi_tt * we need one per port. */ - bitmap_size = DWC2_ELEMENTS_PER_LS_BITMAP * - sizeof(dwc_tt->periodic_bitmaps[0]); + bitmap_size = + flex_array_size(dwc_tt, periodic_bitmaps, + DWC2_ELEMENTS_PER_LS_BITMAP); if (urb->dev->tt->multi) bitmap_size *= urb->dev->tt->hub->maxchild;