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 C6A27C35242 for ; Tue, 11 Feb 2020 21:44:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A6B2206D7 for ; Tue, 11 Feb 2020 21:44:17 +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="fKj5Y5hx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727567AbgBKVoQ (ORCPT ); Tue, 11 Feb 2020 16:44:16 -0500 Received: from gateway36.websitewelcome.com ([192.185.188.18]:39150 "EHLO gateway36.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727043AbgBKVoQ (ORCPT ); Tue, 11 Feb 2020 16:44:16 -0500 X-Greylist: delayed 2916 seconds by postgrey-1.27 at vger.kernel.org; Tue, 11 Feb 2020 16:44:16 EST Received: from cm14.websitewelcome.com (cm14.websitewelcome.com [100.42.49.7]) by gateway36.websitewelcome.com (Postfix) with ESMTP id 1BF4D40BC0795 for ; Tue, 11 Feb 2020 14:09:40 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 1cZHjIfMOXVkQ1cZIjgzwJ; Tue, 11 Feb 2020 14:55:40 -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=Zjc5LElXJ0zIygghxh2TaQQ5QMBnKhOZ9bRBJCzRtXs=; b=fKj5Y5hxtG77C4OrRGtRsmqzFH LmOdqavyDRDgSomroylBrffEtkaEUQlF/iwt2phvzghztPuyMqar6XMggvExMLKHjY9uj184VB4Mf 17Q8Ko8/U6QvGAbIGbebs6knEZuUnfu9z8+TGrA9OVskmBEcAbFjJzi1hCZiM9vx5vmaYxidtkLed baps6upgIypNw/lIsT1kq/aErDchueSF04reoDkrhxEQdCfob2PsTZhrLbigDDOp2Naeweh6Y4BcJ nkMbbK9GuLdHBcrYWzoyztdteIRPM/Ilp3Vxm1MTPwoxtcjUMH5XzPVeRiwu+KpqDLu0zUUy/oG1l G3MCiGjw==; Received: from [200.68.140.36] (port=27335 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1j1cZG-001zvC-G4; Tue, 11 Feb 2020 14:55:38 -0600 Date: Tue, 11 Feb 2020 14:58:13 -0600 From: "Gustavo A. R. Silva" To: Andrew Morton Cc: linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] lib/ts_fsm: Replace zero-length array with flexible-array member Message-ID: <20200211205813.GA25602@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: 1j1cZG-001zvC-G4 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [200.68.140.36]:27335 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 47 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_fsm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/ts_fsm.c b/lib/ts_fsm.c index 69557c74ef9f..f7aed7b6f3fe 100644 --- a/lib/ts_fsm.c +++ b/lib/ts_fsm.c @@ -36,7 +36,7 @@ struct ts_fsm { unsigned int ntokens; - struct ts_fsm_token tokens[0]; + struct ts_fsm_token tokens[]; }; /* other values derived from ctype.h */ -- 2.25.0