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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 E4DE9C433DF for ; Tue, 9 Jun 2020 06:47:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFB2E207C3 for ; Tue, 9 Jun 2020 06:47:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727988AbgFIGrH (ORCPT ); Tue, 9 Jun 2020 02:47:07 -0400 Received: from smtprelay0022.hostedemail.com ([216.40.44.22]:43134 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726917AbgFIGrH (ORCPT ); Tue, 9 Jun 2020 02:47:07 -0400 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay05.hostedemail.com (Postfix) with ESMTP id E1047180424AA; Tue, 9 Jun 2020 06:47:05 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: face18_3117c7126dc0 X-Filterd-Recvd-Size: 2021 Received: from XPS-9350.home (unknown [47.151.136.130]) (Authenticated sender: joe@perches.com) by omf01.hostedemail.com (Postfix) with ESMTPA; Tue, 9 Jun 2020 06:47:04 +0000 (UTC) Message-ID: Subject: Re: [PATCH v2] overflow.h: Add flex_array_size() helper From: Joe Perches To: "Gustavo A. R. Silva" , Kees Cook Cc: linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Date: Mon, 08 Jun 2020 23:47:03 -0700 In-Reply-To: <20200609012233.GA3371@embeddedor> References: <20200609012233.GA3371@embeddedor> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.36.2-0ubuntu1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2020-06-08 at 20:22 -0500, Gustavo A. R. Silva wrote: > Add flex_array_size() helper for the calculation of the size, in bytes, > of a flexible array member contained within an enclosing structure. [] > diff --git a/include/linux/overflow.h b/include/linux/overflow.h [] > +/** > + * flex_array_size() - Calculate size, in bytes, of a flexible array member > + * within an enclosing structure. Read on for more details. IMO: "Read on for more details" isn't useful here. Perhaps better would be something like: * flex_array_size() - size of a flexible array (sizeof(typeof(member)) * count) > + * > + * @p: Pointer to the structure. > + * @member: Name of the flexible array member. > + * @count: Number of elements in the array. > + * > + * Calculates size, in bytes, of a flexible array @member of @count elements IMO: "in bytes, " is redundant. size is always bytes. > + * within structure @p. > + * > + * Return: number of bytes needed or SIZE_MAX on overflow. > + */ > +#define flex_array_size(p, member, count) \ > + array_size(count, \ > + sizeof(*(p)->member) + __must_be_array((p)->member)) > + > #endif /* __LINUX_OVERFLOW_H */