From patchwork Tue Feb 11 23:21:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 11377141 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D809614E3 for ; Tue, 11 Feb 2020 23:19:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B65082086A for ; Tue, 11 Feb 2020 23:19:17 +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="zhCYtFoM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727916AbgBKXTQ (ORCPT ); Tue, 11 Feb 2020 18:19:16 -0500 Received: from gateway21.websitewelcome.com ([192.185.45.175]:36420 "EHLO gateway21.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727597AbgBKXTQ (ORCPT ); Tue, 11 Feb 2020 18:19:16 -0500 Received: from cm17.websitewelcome.com (cm17.websitewelcome.com [100.42.49.20]) by gateway21.websitewelcome.com (Postfix) with ESMTP id 37B88400C8BAD for ; Tue, 11 Feb 2020 17:19:15 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 1eoFjkE8vAGTX1eoFjwbP9; Tue, 11 Feb 2020 17:19:15 -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=3ukPiRuumhyjQE2a3H1TwfC2YcfYXQVvQ3fpynTB+oY=; b=zhCYtFoMtUJqzr7Me6tN01lX5t v5qecBOHt3Ar+8zQLmqaPAGSNVU5RY9XTgKOsckb9Jd48kpw7XZjgi5A0TDsNRMqze4IdDUHDkh0R k5NyvGVCK25spCDFLqUOgtdLAbaEkFmbUtocAq7p3TUKoN2jMZ5RwehThuzYwKIcycrYhCAOjiVE2 RTD2njB1zPS+odqA7+Ag1Wu9mhYMFfBjM9WZhi09JGjs0dB2aP/7RLGxoHX1qf5QIIiLUYETzdyrx w7DVPbU4zHgrJIJV/nZUvDpBFN4mgaTBh3QqkjFcutaQy9iwpoL4z27rXor55yY/eSVixqXJRRhec Wf1J92Ig==; Received: from [200.68.140.36] (port=13213 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1j1eoD-003Z4z-Ra; Tue, 11 Feb 2020 17:19:13 -0600 Date: Tue, 11 Feb 2020 17:21:48 -0600 From: "Gustavo A. R. Silva" To: Matthieu CASTET , Stanislaw Gruszka , Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] USB: atm: Replace zero-length array with flexible-array member Message-ID: <20200211232148.GA20644@embeddedor> MIME-Version: 1.0 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: 1j1eoD-003Z4z-Ra X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [200.68.140.36]:13213 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 35 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@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 --- drivers/usb/atm/ueagle-atm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/atm/ueagle-atm.c b/drivers/usb/atm/ueagle-atm.c index 2754b4ce7136..25cf94131987 100644 --- a/drivers/usb/atm/ueagle-atm.c +++ b/drivers/usb/atm/ueagle-atm.c @@ -394,7 +394,7 @@ struct l1_code { u8 string_header[E4_L1_STRING_HEADER]; u8 page_number_to_block_index[E4_MAX_PAGE_NUMBER]; struct block_index page_header[E4_NO_SWAPPAGE_HEADERS]; - u8 code[0]; + u8 code[]; } __packed; /* structures describing a block within a DSP page */