From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:52832 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753415AbdJQPRt (ORCPT ); Tue, 17 Oct 2017 11:17:49 -0400 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v9HFFKFr089472 for ; Tue, 17 Oct 2017 11:17:49 -0400 Received: from e06smtp15.uk.ibm.com (e06smtp15.uk.ibm.com [195.75.94.111]) by mx0a-001b2d01.pphosted.com with ESMTP id 2dnk894dq8-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 17 Oct 2017 11:17:49 -0400 Received: from localhost by e06smtp15.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 17 Oct 2017 16:17:47 +0100 Subject: Re: [PATCH 3/4] char/tpm: Improve a size determination in nine functions From: Mimi Zohar To: Julia Lawall Cc: Alexander.Steffen@infineon.com, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, andriy.shevchenko@linux.intel.com, elfring@users.sourceforge.net, linux-integrity@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, benh@kernel.crashing.org, clabbe.montjoie@gmail.com, jarkko.sakkinen@linux.intel.com, jgunthorpe@obsidianresearch.com, jsnitsel@redhat.com, kgold@linux.vnet.ibm.com, mpe@ellerman.id.au, nayna@linux.vnet.ibm.com, paulus@samba.org, PeterHuewe@gmx.de, Stefan Berger Date: Tue, 17 Oct 2017 11:17:33 -0400 In-Reply-To: References: <1d3516a2-a8e6-9e95-d438-f115fac84c7f@users.sourceforge.net> <83a166af-aecc-649d-dfe3-a72245345209@users.sourceforge.net> <1508238182.16112.475.camel@linux.intel.com> <1508244757.4234.60.camel@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Message-Id: <1508253453.4234.81.camel@linux.vnet.ibm.com> Sender: linux-integrity-owner@vger.kernel.org List-ID: On Tue, 2017-10-17 at 14:58 +0200, Julia Lawall wrote: > > On Tue, 17 Oct 2017, Mimi Zohar wrote: > > > On Tue, 2017-10-17 at 11:50 +0000, Alexander.Steffen@infineon.com > > wrote: > > > > > Replace the specification of data structures by pointer dereferences > > > > > as the parameter for the operator "sizeof" to make the corresponding > > > > > size > > > > > determination a bit safer according to the Linux coding style > > > > > convention. > > > > > > > > > > > > This patch does one style in favor of the other. > > > > > > I actually prefer that style, so I'd welcome this change :) > > > > Style changes should be reviewed and documented, like any other code > > change, and added to Documentation/process/coding-style.rst or an > > equivalent file. > > Actually, it has been there for many years: > > 14) Allocating memory > --------------------- > ... > The preferred form for passing a size of a struct is the following: > > .. code-block:: c > > p = kmalloc(sizeof(*p), ...); > > The alternative form where struct name is spelled out hurts readability and > introduces an opportunity for a bug when the pointer variable type is changed > but the corresponding sizeof that is passed to a memory allocator is not. True, thanks for the reminder. Is this common in new code? Is there a script/ or some other automated way of catching this usage before patches are upstreamed? Just as you're doing here, the patch description should reference this in the patch description. Mimi