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 A4F7DC35242 for ; Tue, 11 Feb 2020 21:01:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7795A206D6 for ; Tue, 11 Feb 2020 21:01:56 +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="NckG9P0+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729369AbgBKVBz (ORCPT ); Tue, 11 Feb 2020 16:01:55 -0500 Received: from gateway21.websitewelcome.com ([192.185.45.155]:12210 "EHLO gateway21.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727785AbgBKVBz (ORCPT ); Tue, 11 Feb 2020 16:01:55 -0500 Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway21.websitewelcome.com (Postfix) with ESMTP id 009B7400D73F2 for ; Tue, 11 Feb 2020 15:01:54 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 1cfJj7R0kEfyq1cfJjHPJM; Tue, 11 Feb 2020 15:01:53 -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=ljMqRoFvDt0cvQi9PMh9cAqYCAMvtHVlBbjz5BB0km8=; b=NckG9P0+8Z9/rmG3tEeQ3buUQ9 q4OOlbCmZWYJi9YYVOdARn//3viHJSlswfY0eTwBnAYhc95EIDY+PTYSK7kXT6gu9V4HiepK1mdha QSTfyW1fyFw4VkH+Ox2a94oi/jklzBVMaJOeu81hrpszx9wOFEbpAW8HitnKkpjL7iVGDm5p3F5f4 1pNwIqOxknrrjoNeWspLnrquQxsXPZVndDwIdrSK5c1iDN4C2YmgstZaVlbkN2GvbTQub+5dgUMgT nFKr5GWwM1FctusT3HDbIlh7aB88fmMWn8iyTJtTZgLlZfKVb49MRpzjv/QGz8oip3TC18Jq8E2HA kFJYSYEw==; Received: from [200.68.140.36] (port=31327 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1j1cfI-0025UI-7K; Tue, 11 Feb 2020 15:01:52 -0600 Date: Tue, 11 Feb 2020 15:04:27 -0600 From: "Gustavo A. R. Silva" To: John Johansen , James Morris , "Serge E. Hallyn" Cc: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] apparmor: Replace zero-length array with flexible-array member Message-ID: <20200211210427.GA28952@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: 1j1cfI-0025UI-7K X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [200.68.140.36]:31327 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 5 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 --- security/apparmor/apparmorfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index fefee040bf79..cc81080efb63 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -804,7 +804,7 @@ static ssize_t query_label(char *buf, size_t buf_len, struct multi_transaction { struct kref count; ssize_t size; - char data[0]; + char data[]; }; #define MULTI_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct multi_transaction)) -- 2.25.0