From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: uwb: use struct_size() in kzalloc() From: "Gustavo A. R. Silva" Message-Id: <20190108162700.GA27100@embeddedor> Date: Tue, 8 Jan 2019 10:27:00 -0600 To: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" List-ID: T25lIG9mIHRoZSBtb3JlIGNvbW1vbiBjYXNlcyBvZiBhbGxvY2F0aW9uIHNpemUgY2FsY3VsYXRp b25zIGlzIGZpbmRpbmcgdGhlCnNpemUgb2YgYSBzdHJ1Y3R1cmUgdGhhdCBoYXMgYSB6ZXJvLXNp emVkIGFycmF5IGF0IHRoZSBlbmQsIGFsb25nIHdpdGggbWVtb3J5CmZvciBzb21lIG51bWJlciBv ZiBlbGVtZW50cyBmb3IgdGhhdCBhcnJheS4gRm9yIGV4YW1wbGU6CgpzdHJ1Y3QgZm9vIHsKICAg IGludCBzdHVmZjsKICAgIHZvaWQgKmVudHJ5W107Cn07CgppbnN0YW5jZSA9IGt6YWxsb2Moc2l6 ZW9mKHN0cnVjdCBmb28pICsgc2l6ZW9mKHZvaWQgKikgKiBjb3VudCwgR0ZQX0tFUk5FTCk7CgpJ bnN0ZWFkIG9mIGxlYXZpbmcgdGhlc2Ugb3Blbi1jb2RlZCBhbmQgcHJvbmUgdG8gdHlwZSBtaXN0 YWtlcywgd2UgY2FuIG5vdwp1c2UgdGhlIG5ldyBzdHJ1Y3Rfc2l6ZSgpIGhlbHBlcjoKCmluc3Rh bmNlID0ga3phbGxvYyhzdHJ1Y3Rfc2l6ZShpbnN0YW5jZSwgZW50cnksIGNvdW50KSwgR0ZQX0tF Uk5FTCk7CgpUaGlzIGNvZGUgd2FzIGRldGVjdGVkIHdpdGggdGhlIGhlbHAgb2YgQ29jY2luZWxs ZS4KClNpZ25lZC1vZmYtYnk6IEd1c3Rhdm8gQS4gUi4gU2lsdmEgPGd1c3Rhdm9AZW1iZWRkZWRv ci5jb20+Ci0tLQogZHJpdmVycy91d2IvZHJwLWllLmMgfCA1ICsrLS0tCiAxIGZpbGUgY2hhbmdl ZCwgMiBpbnNlcnRpb25zKCspLCAzIGRlbGV0aW9ucygtKQoKZGlmZiAtLWdpdCBhL2RyaXZlcnMv dXdiL2RycC1pZS5jIGIvZHJpdmVycy91d2IvZHJwLWllLmMKaW5kZXggMWQyYTkzOWNmY2Y4Li5l ZDk5M2UzNjM0NzIgMTAwNjQ0Ci0tLSBhL2RyaXZlcnMvdXdiL2RycC1pZS5jCisrKyBiL2RyaXZl cnMvdXdiL2RycC1pZS5jCkBAIC0xMjUsOSArMTI1LDggQEAgc3RhdGljIHN0cnVjdCB1d2JfaWVf ZHJwICp1d2JfZHJwX2llX2FsbG9jKHZvaWQpCiB7CiAJc3RydWN0IHV3Yl9pZV9kcnAgKmRycF9p ZTsKIAotCWRycF9pZSA9IGt6YWxsb2Moc2l6ZW9mKHN0cnVjdCB1d2JfaWVfZHJwKSArCi0JCQlV V0JfTlVNX1pPTkVTICogc2l6ZW9mKHN0cnVjdCB1d2JfZHJwX2FsbG9jKSwKLQkJCUdGUF9LRVJO RUwpOworCWRycF9pZSA9IGt6YWxsb2Moc3RydWN0X3NpemUoZHJwX2llLCBhbGxvY3MsIFVXQl9O VU1fWk9ORVMpLAorCQkJIEdGUF9LRVJORUwpOwogCWlmIChkcnBfaWUpCiAJCWRycF9pZS0+aGRy LmVsZW1lbnRfaWQgPSBVV0JfSUVfRFJQOwogCXJldHVybiBkcnBfaWU7Cg== 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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, 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 48488C43387 for ; Tue, 8 Jan 2019 16:48:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1150021019 for ; Tue, 8 Jan 2019 16:48:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729209AbfAHQsm (ORCPT ); Tue, 8 Jan 2019 11:48:42 -0500 Received: from gateway36.websitewelcome.com ([192.185.197.22]:31098 "EHLO gateway36.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729164AbfAHQsl (ORCPT ); Tue, 8 Jan 2019 11:48:41 -0500 X-Greylist: delayed 1294 seconds by postgrey-1.27 at vger.kernel.org; Tue, 08 Jan 2019 11:48:40 EST Received: from cm17.websitewelcome.com (cm17.websitewelcome.com [100.42.49.20]) by gateway36.websitewelcome.com (Postfix) with ESMTP id 70F01400D160F for ; Tue, 8 Jan 2019 09:39:08 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id guDagVH9j90onguDagzUAC; Tue, 08 Jan 2019 10:27:06 -0600 X-Authority-Reason: nr=8 Received: from [189.250.130.205] (port=53168 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gguDY-001pZ2-VQ; Tue, 08 Jan 2019 10:27:05 -0600 Date: Tue, 8 Jan 2019 10:27:00 -0600 From: "Gustavo A. R. Silva" To: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] uwb: use struct_size() in kzalloc() Message-ID: <20190108162700.GA27100@embeddedor> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii 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: 1gguDY-001pZ2-VQ X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.130.205]:53168 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 22 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- drivers/uwb/drp-ie.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/uwb/drp-ie.c b/drivers/uwb/drp-ie.c index 1d2a939cfcf8..ed993e363472 100644 --- a/drivers/uwb/drp-ie.c +++ b/drivers/uwb/drp-ie.c @@ -125,9 +125,8 @@ static struct uwb_ie_drp *uwb_drp_ie_alloc(void) { struct uwb_ie_drp *drp_ie; - drp_ie = kzalloc(sizeof(struct uwb_ie_drp) + - UWB_NUM_ZONES * sizeof(struct uwb_drp_alloc), - GFP_KERNEL); + drp_ie = kzalloc(struct_size(drp_ie, allocs, UWB_NUM_ZONES), + GFP_KERNEL); if (drp_ie) drp_ie->hdr.element_id = UWB_IE_DRP; return drp_ie; -- 2.20.1