From patchwork Fri Jan 4 21:22:09 2019 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: 10748835 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AEF42746 for ; Fri, 4 Jan 2019 21:22:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 94CF328585 for ; Fri, 4 Jan 2019 21:22:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 88D9D287A8; Fri, 4 Jan 2019 21:22:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1BE7328585 for ; Fri, 4 Jan 2019 21:22:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726168AbfADVWN (ORCPT ); Fri, 4 Jan 2019 16:22:13 -0500 Received: from gateway24.websitewelcome.com ([192.185.50.84]:16068 "EHLO gateway24.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725987AbfADVWN (ORCPT ); Fri, 4 Jan 2019 16:22:13 -0500 Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway24.websitewelcome.com (Postfix) with ESMTP id 66EE93CFEC for ; Fri, 4 Jan 2019 15:22:12 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id fWuygtNWA2PzOfWuygZ7A9; Fri, 04 Jan 2019 15:22:12 -0600 X-Authority-Reason: nr=8 Received: from [189.250.130.205] (port=41040 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gfWux-002x5R-D2; Fri, 04 Jan 2019 15:22:11 -0600 Date: Fri, 4 Jan 2019 15:22:09 -0600 From: "Gustavo A. R. Silva" To: Matthew Wilcox , Hannes Reinecke , "James E.J. Bottomley" , "Martin K. Petersen" Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] scsi: advansys: use struct_size() in kzalloc() Message-ID: <20190104212209.GA15250@embeddedor> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.250.130.205 X-Source-L: No X-Exim-ID: 1gfWux-002x5R-D2 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.130.205]:41040 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 16 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 Reviewed-by: Hannes Reinecke --- drivers/scsi/advansys.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/advansys.c b/drivers/scsi/advansys.c index d37584403c33..6c274e6e1c33 100644 --- a/drivers/scsi/advansys.c +++ b/drivers/scsi/advansys.c @@ -7576,8 +7576,8 @@ static int asc_build_req(struct asc_board *boardp, struct scsi_cmnd *scp, return ASC_ERROR; } - asc_sg_head = kzalloc(sizeof(asc_scsi_q->sg_head) + - use_sg * sizeof(struct asc_sg_list), GFP_ATOMIC); + asc_sg_head = kzalloc(struct_size(asc_sg_head, sg_list, use_sg), + GFP_ATOMIC); if (!asc_sg_head) { scsi_dma_unmap(scp); scp->result = HOST_BYTE(DID_SOFT_ERROR);