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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT 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 8156CC43381 for ; Sun, 17 Feb 2019 23:24:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 599902184E for ; Sun, 17 Feb 2019 23:24:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727406AbfBQXYN (ORCPT ); Sun, 17 Feb 2019 18:24:13 -0500 Received: from mail.us.es ([193.147.175.20]:44252 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727355AbfBQXYK (ORCPT ); Sun, 17 Feb 2019 18:24:10 -0500 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id A9F2E1B8427 for ; Mon, 18 Feb 2019 00:24:02 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 96DFADA863 for ; Mon, 18 Feb 2019 00:24:02 +0100 (CET) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 8C02CDA84E; Mon, 18 Feb 2019 00:24:02 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 9D40DDA844; Mon, 18 Feb 2019 00:24:00 +0100 (CET) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Mon, 18 Feb 2019 00:24:00 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from salvia.here (sys.soleta.eu [212.170.55.40]) (Authenticated sender: pneira@us.es) by entrada.int (Postfix) with ESMTPA id 71BCF4265A2F; Mon, 18 Feb 2019 00:24:00 +0100 (CET) X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org Subject: [PATCH 07/11] netfilter: xt_recent: Use struct_size() in kvzalloc() Date: Mon, 18 Feb 2019 00:23:53 +0100 Message-Id: <20190217232357.29858-8-pablo@netfilter.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190217232357.29858-1-pablo@netfilter.org> References: <20190217232357.29858-1-pablo@netfilter.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: "Gustavo A. R. Silva" 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[]; }; size = sizeof(struct foo) + count * sizeof(void *); instance = alloc(size, GFP_KERNEL) Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: size = struct_size(instance, entry, count); instance = alloc(size, GFP_KERNEL) Notice that, in this case, variable sz is not necessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva Signed-off-by: Pablo Neira Ayuso --- net/netfilter/xt_recent.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c index f44de4bc2100..1664d2ec8b2f 100644 --- a/net/netfilter/xt_recent.c +++ b/net/netfilter/xt_recent.c @@ -337,7 +337,6 @@ static int recent_mt_check(const struct xt_mtchk_param *par, unsigned int nstamp_mask; unsigned int i; int ret = -EINVAL; - size_t sz; net_get_random_once(&hash_rnd, sizeof(hash_rnd)); @@ -387,8 +386,7 @@ static int recent_mt_check(const struct xt_mtchk_param *par, goto out; } - sz = sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size; - t = kvzalloc(sz, GFP_KERNEL); + t = kvzalloc(struct_size(t, iphash, ip_list_hash_size), GFP_KERNEL); if (t == NULL) { ret = -ENOMEM; goto out; -- 2.11.0