From patchwork Tue Feb 25 02:08:04 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: 11402413 X-Patchwork-Delegate: kvalo@adurom.com 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 07E2E13A4 for ; Tue, 25 Feb 2020 02:53:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D93E821927 for ; Tue, 25 Feb 2020 02:53:56 +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="SDfjbEqU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728885AbgBYCx4 (ORCPT ); Mon, 24 Feb 2020 21:53:56 -0500 Received: from gateway36.websitewelcome.com ([192.185.194.2]:39900 "EHLO gateway36.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728725AbgBYCx4 (ORCPT ); Mon, 24 Feb 2020 21:53:56 -0500 X-Greylist: delayed 1500 seconds by postgrey-1.27 at vger.kernel.org; Mon, 24 Feb 2020 21:53:55 EST Received: from cm11.websitewelcome.com (cm11.websitewelcome.com [100.42.49.5]) by gateway36.websitewelcome.com (Postfix) with ESMTP id 1CE85400D1628 for ; Mon, 24 Feb 2020 19:21:06 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 6PbojKuJ7Sl8q6Pbzjzw42; Mon, 24 Feb 2020 20:06:20 -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=3WYY4D95dFsGR6aMI/L2pR572DKPC2ZtgZvA51FyZmc=; b=SDfjbEqUWa5eyJtudos2VU69K3 slC/oG4O9+M6lqicfB/Ypvnl9pHtHkvcPAIjDbTrwGhc8GHF4Au8ftHWr+66MZVLJVQ7dZ0OsGH1Z 9Sucy77xWuZhLOkv/4ujdkydQ1ibfudhitglXMVtz1bJoWHMjxniLqb9N2jd5UPyR8eJRymHlK8tX 4RZghqUUz+K6pn6HbGp6HZAQQf85GBWGNLEbaF6n0Ny1YItVZmR0769hFHowRnXBb3oLJFXbxGYVN o/70KaI/Ig0ILP2MtfxHPPJml1+3We6thtdY1fFwKJch3vb1g90h7wwsGjfOgCVaisGZQnWeL3pvS ZtP5SOxQ==; Received: from [201.166.191.97] (port=60674 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1j6PbT-003Hcz-Ke; Mon, 24 Feb 2020 20:05:44 -0600 Date: Mon, 24 Feb 2020 20:08:04 -0600 From: "Gustavo A. R. Silva" To: Arend van Spriel , Franky Lin , Hante Meuleman , Chi-Hsien Lin , Wright Feng , Kalle Valo , "David S. Miller" Cc: linux-wireless@vger.kernel.org, brcm80211-dev-list.pdl@broadcom.com, brcm80211-dev-list@cypress.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH][next] brcmfmac: Replace zero-length array with flexible-array member Message-ID: <20200225020804.GA9428@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: 201.166.191.97 X-Source-L: No X-Exim-ID: 1j6PbT-003Hcz-Ke X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [201.166.191.97]:60674 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 17 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@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 inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] 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 Acked-by: Arend van Spriel --- drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.h | 2 +- drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.h index 3347439543bb..46c66415b4a6 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.h +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.h @@ -60,7 +60,7 @@ struct brcmf_fw_request { u16 bus_nr; u32 n_items; const char *board_type; - struct brcmf_fw_item items[0]; + struct brcmf_fw_item items[]; }; struct brcmf_fw_name { diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c index 79c8a858b6d6..a5cced2c89ac 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c @@ -32,7 +32,7 @@ struct brcmf_fweh_queue_item { u8 ifaddr[ETH_ALEN]; struct brcmf_event_msg_be emsg; u32 datalen; - u8 data[0]; + u8 data[]; }; /**