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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT 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 7E481C43387 for ; Sat, 12 Jan 2019 01:47:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C51E2184C for ; Sat, 12 Jan 2019 01:47:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WYzLVgU8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726506AbfALBrb (ORCPT ); Fri, 11 Jan 2019 20:47:31 -0500 Received: from mail-pl1-f196.google.com ([209.85.214.196]:34736 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726227AbfALBra (ORCPT ); Fri, 11 Jan 2019 20:47:30 -0500 Received: by mail-pl1-f196.google.com with SMTP id w4so7539172plz.1; Fri, 11 Jan 2019 17:47:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=7ahfG1fhpR6sKoLe8rUEuXte8fjAZS1mXKqHwDqjHMg=; b=WYzLVgU8oBXcQo2B6b9lAcpdxWbsXRirXq7/3gD2JzyUdXUFVDwraJ3G27Pz+Jpb8R HsPKszhjQgH3Sud71P2uY22aqYWdDAqpQr58M5wsQKnuQZSyzeGeYyFx43uq+J67O7uM whIEonanS+Zxc5yJAPFsnlnNHaXSg6gvujSfDgIj11lybCSmIQkUds8TtAY3p+VbZRvV wjaU3azlyCpFBV9S50OE65EDT3Atecm9EqcSbD5T0j0aR9+H56N2LkFhYfZtxkswRRnP DQp2gmaPkNSXccoRxaU21vzocMt5N8Lov7BmQBb5vnzIHVDpSQtKygbedrqLATMMFrez nu8g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=7ahfG1fhpR6sKoLe8rUEuXte8fjAZS1mXKqHwDqjHMg=; b=uepV6NqhsLLrW2ES4P6FT1/UT2uZ99qMIYByA2N7+zF6V/q14B5PMpU26QTcI/bqvh aZzMt4ZZ7SQHx32xRzXvs5ExITurjixElxsqN04/sVmAJgJc12f7DvgGBqj92JOD2rJ/ fxY7WgBJiL76pRo8qQM7LUdni7MMhXBl5Cfi3jPmLr1QcsMNamY9ETEWDyR1jot18lTR t518q69fvjWDk07uzEKNZWmygcEsZCLSkB1Cbu6KK1Upd/3idmWY6BV+Q4XbSx4nqZzz sWiwFz6Z7AQicUslj4cSHyBKf77soLaVcbOFrE/Q5228s2tK3bKwgparZecEo3pBxNQx 8Faw== X-Gm-Message-State: AJcUukcCz6j6yy3DNUxtPDCCuo191R2o0LDqNW14Mlf81ogtGtgm/jVl XY8fuRJsjZw0lewvlcAh7z6FYDrP X-Google-Smtp-Source: ALg8bN6qAXLqsdEgK51q8VJo/bgY26A5oGfQGYey7fW1d+FVxZaGCPXXnC+gBKekDs/9fkS4s5dN2A== X-Received: by 2002:a17:902:108a:: with SMTP id c10mr17134232pla.131.1547257649279; Fri, 11 Jan 2019 17:47:29 -0800 (PST) Received: from dtor-ws ([2620:15c:202:201:3adc:b08c:7acc:b325]) by smtp.gmail.com with ESMTPSA id t29sm122649661pfa.158.2019.01.11.17.47.28 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 11 Jan 2019 17:47:28 -0800 (PST) Date: Fri, 11 Jan 2019 17:47:26 -0800 From: Dmitry Torokhov To: "Gustavo A. R. Silva" Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Input: tca6416-keypad: use struct_size() in kzalloc() Message-ID: <20190112014726.GB122403@dtor-ws> References: <20190108152816.GA7486@embeddedor> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190108152816.GA7486@embeddedor> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 08, 2019 at 09:28:16AM -0600, Gustavo A. R. Silva wrote: > One of the more common cases of allocation size calculations is finding the > size of a structure that has a zero-sized array at the end, along with memory > for some number of elements for that array. For example: > > struct foo { > int stuff; > void *entry[]; > }; > > instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL); > > Instead of leaving these open-coded and prone to type mistakes, we can now > use the new struct_size() helper: > > instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); > > This code was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva Applied, thank you. > --- > drivers/input/keyboard/tca6416-keypad.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/drivers/input/keyboard/tca6416-keypad.c b/drivers/input/keyboard/tca6416-keypad.c > index dc983ab6c0ad..cdeef180aead 100644 > --- a/drivers/input/keyboard/tca6416-keypad.c > +++ b/drivers/input/keyboard/tca6416-keypad.c > @@ -219,9 +219,7 @@ static int tca6416_keypad_probe(struct i2c_client *client, > return -EINVAL; > } > > - chip = kzalloc(sizeof(struct tca6416_keypad_chip) + > - pdata->nbuttons * sizeof(struct tca6416_button), > - GFP_KERNEL); > + chip = kzalloc(struct_size(chip, buttons, pdata->nbuttons), GFP_KERNEL); > input = input_allocate_device(); > if (!chip || !input) { > error = -ENOMEM; > -- > 2.20.1 > -- Dmitry