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=-13.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 3C4B0C35242 for ; Tue, 11 Feb 2020 20:57:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 10EFA206D6 for ; Tue, 11 Feb 2020 20:57:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=embeddedor.com header.i=@embeddedor.com header.b="DdRN6YlC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731923AbgBKU5Q (ORCPT ); Tue, 11 Feb 2020 15:57:16 -0500 Received: from gateway22.websitewelcome.com ([192.185.46.187]:20193 "EHLO gateway22.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728369AbgBKU5P (ORCPT ); Tue, 11 Feb 2020 15:57:15 -0500 X-Greylist: delayed 712 seconds by postgrey-1.27 at vger.kernel.org; Tue, 11 Feb 2020 15:57:14 EST Received: from cm17.websitewelcome.com (cm17.websitewelcome.com [100.42.49.20]) by gateway22.websitewelcome.com (Postfix) with ESMTP id 71888A4CB for ; Tue, 11 Feb 2020 14:57:14 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 1caojhTFYAGTX1caojtrfW; Tue, 11 Feb 2020 14:57:14 -0600 X-Authority-Reason: nr=8 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=embeddedor.com; s=default; h=Content-Type:MIME-Version:Message-ID:Subject: Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=V1Z404XEtIf1we24S0h9I5bmknoegUWcJTRAMxr/esg=; b=DdRN6YlC2f8LqTpehtxTjdqX3X rgA1gHkpoYex4df+5mrHFGSlZFmOirJ/JtCUfUJLp+appbbG+F+anV+tCHPBg7MZplZgDF994oLM5 ElJFQ7OH8EuBT3uDLLkd29IQWejPrvIrXfdfqX+9tCU3TawlWJ/SEpxoHxLR+jFD+wOxdeCieyrPd zIQXIJR/w5LnI3jMeEj7jWn4i5ZaRmg2z+P8m1xsksQGD1eDLI/S7vUWiv1gntdrUEv8Uss3owSiN q5dfn7lhSUBWZoZVHRqOF47hsG1e98J1duSYcqpS9RfgF1u1yGmxXd10FjdDfX3uMkuFKR2LF/XSx Zhitvt0Q==; Received: from [200.68.140.36] (port=19003 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1j1can-0020zm-3i; Tue, 11 Feb 2020 14:57:13 -0600 Date: Tue, 11 Feb 2020 14:59:48 -0600 From: "Gustavo A. R. Silva" To: Andrew Morton Cc: linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] lib/ts_kmp: Replace zero-length array with flexible-array member Message-ID: <20200211205948.GA26459@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: 200.68.140.36 X-Source-L: No X-Exim-ID: 1j1can-0020zm-3i X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [200.68.140.36]:19003 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 49 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 The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertenly introduced[3] to the codebase from now on. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva --- lib/ts_kmp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/ts_kmp.c b/lib/ts_kmp.c index ffbe66cbb0ed..9dd5e708630e 100644 --- a/lib/ts_kmp.c +++ b/lib/ts_kmp.c @@ -40,7 +40,7 @@ struct ts_kmp { u8 * pattern; unsigned int pattern_len; - unsigned int prefix_tbl[0]; + unsigned int prefix_tbl[]; }; static unsigned int kmp_find(struct ts_config *conf, struct ts_state *state) -- 2.25.0