From patchwork Thu Mar 19 22:22:29 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: 11448155 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 3114E1668 for ; Thu, 19 Mar 2020 22:44:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 108652076C for ; Thu, 19 Mar 2020 22:44:23 +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="l3k+wfE4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727407AbgCSWoW (ORCPT ); Thu, 19 Mar 2020 18:44:22 -0400 Received: from gateway30.websitewelcome.com ([192.185.197.25]:30219 "EHLO gateway30.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726867AbgCSWoW (ORCPT ); Thu, 19 Mar 2020 18:44:22 -0400 X-Greylist: delayed 1308 seconds by postgrey-1.27 at vger.kernel.org; Thu, 19 Mar 2020 18:44:21 EDT Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway30.websitewelcome.com (Postfix) with ESMTP id 88DF92912 for ; Thu, 19 Mar 2020 17:22:32 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id F3YejD6DHEfyqF3YejD8fM; Thu, 19 Mar 2020 17:22:32 -0500 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=Fch2gw+FxFOXUz75GYw483nOatBMsFwMZSrEf6kFfTg=; b=l3k+wfE4lVqBWzoz4AH1Y3aB4X SNG1oTH5L8odnCiD4YykyzsTml/8wJx0Nh3HQ5xOyW9QdscofmWrhUoksFaYLna1vptrw4dH7u0OR JQ/z2YgbjGQYyiTjWegOVTfZTG+G0+mabbHUMsPZs9XhLRksK+sWYqVAlQcBuaPl/qkoYYGLyXrB5 PC3zlrvGU52YVAz6nur+atgPOezOttLLEeDD++9BdlbxykWlKNZRh1gBk7e2iJXpdJx7To+tSUoTe XgzlFwksvHPa4oQpM1NfeFzE1xSw8FcfB+JxFOqiKEJ9k1tEzdDLc1Kylt1gxrEJkcj3oMD0MAnj9 bU+P7o4A==; Received: from cablelink-189-218-116-241.hosts.intercable.net ([189.218.116.241]:53888 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1jF3Yc-0023qC-18; Thu, 19 Mar 2020 17:22:30 -0500 Date: Thu, 19 Mar 2020 17:22:29 -0500 From: "Gustavo A. R. Silva" To: Stanimir Varbanov , Andy Gross , Bjorn Andersson , Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH][next] media: venus: hfi_msgs.h: Replace zero-length array with flexible-array member Message-ID: <20200319222229.GA19280@embeddedor.com> 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: 189.218.116.241 X-Source-L: No X-Exim-ID: 1jF3Yc-0023qC-18 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: cablelink-189-218-116-241.hosts.intercable.net (embeddedor) [189.218.116.241]:53888 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 13 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@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: Stanimir Varbanov --- drivers/media/platform/qcom/venus/hfi_msgs.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/media/platform/qcom/venus/hfi_msgs.h b/drivers/media/platform/qcom/venus/hfi_msgs.h index 7694b1d25d9d..526d9f5b487b 100644 --- a/drivers/media/platform/qcom/venus/hfi_msgs.h +++ b/drivers/media/platform/qcom/venus/hfi_msgs.h @@ -155,7 +155,7 @@ struct hfi_msg_session_empty_buffer_done_pkt { u32 input_tag; u32 packet_buffer; u32 extradata_buffer; - u32 data[0]; + u32 data[]; }; struct hfi_msg_session_fbd_compressed_pkt { @@ -175,7 +175,7 @@ struct hfi_msg_session_fbd_compressed_pkt { u32 picture_type; u32 packet_buffer; u32 extradata_buffer; - u32 data[0]; + u32 data[]; }; struct hfi_msg_session_fbd_uncompressed_plane0_pkt { @@ -202,7 +202,7 @@ struct hfi_msg_session_fbd_uncompressed_plane0_pkt { u32 picture_type; u32 packet_buffer; u32 extradata_buffer; - u32 data[0]; + u32 data[]; }; struct hfi_msg_session_fbd_uncompressed_plane1_pkt { @@ -211,7 +211,7 @@ struct hfi_msg_session_fbd_uncompressed_plane1_pkt { u32 filled_len; u32 offset; u32 packet_buffer2; - u32 data[0]; + u32 data[]; }; struct hfi_msg_session_fbd_uncompressed_plane2_pkt { @@ -220,7 +220,7 @@ struct hfi_msg_session_fbd_uncompressed_plane2_pkt { u32 filled_len; u32 offset; u32 packet_buffer3; - u32 data[0]; + u32 data[]; }; struct hfi_msg_session_parse_sequence_header_done_pkt {