From patchwork Thu May 7 18:59:35 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: 11534731 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 C499314B4 for ; Thu, 7 May 2020 18:55:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0F5B218AC for ; Thu, 7 May 2020 18:55:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588877711; bh=WD+mKH75WVmomMan20IQTLVrT2j50ndwiS9moo5Kw/8=; h=Date:From:To:Cc:Subject:List-ID:From; b=UbENh6ILU1eLTQO/5elkeIrUBop9Dk67tz/9z2rc3aus4pRqWSiTZoP3MlOxoKPXH xvIvD2TudxD1e53745PZTiFVa7mSGFU/huHTjfb1pLmadocOWHXMI3xVmnFAfJEHqm mx0sQCIs28DyuqwEkPqKoJecLAuCcx9J49sRoG1k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728043AbgEGSzL (ORCPT ); Thu, 7 May 2020 14:55:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:57078 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727904AbgEGSzK (ORCPT ); Thu, 7 May 2020 14:55:10 -0400 Received: from embeddedor (unknown [189.207.59.248]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0BBF520575; Thu, 7 May 2020 18:55:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588877709; bh=WD+mKH75WVmomMan20IQTLVrT2j50ndwiS9moo5Kw/8=; h=Date:From:To:Cc:Subject:From; b=R35Sr5GYmkjS86HqRYoRakM5o3LeRslh2lMRiFYRnFPD58D+ZwSR2jhSc0GVFGbk9 8jn8nGJb+2UbtqlM9ClsT0lQn0uPMKll5IoZrTORcy4vo79FBfVAIHHaQR/ybpmQnJ ytm8S2x5gyH8L0FOp+6RwINmlvuPahT3ZY0NYYjY= Date: Thu, 7 May 2020 13:59:35 -0500 From: "Gustavo A. R. Silva" To: Saeed Mahameed , Leon Romanovsky Cc: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] net/mlx5: Replace zero-length array with flexible-array Message-ID: <20200507185935.GA15169@embeddedor> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@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] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. 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 --- include/linux/mlx5/driver.h | 2 - include/linux/mlx5/mlx5_ifc.h | 66 +++++++++++++++++++++--------------------- include/linux/mlx5/qp.h | 2 - 3 files changed, 35 insertions(+), 35 deletions(-) diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h index 6f8f79ef829b..1a4ba36275de 100644 --- a/include/linux/mlx5/driver.h +++ b/include/linux/mlx5/driver.h @@ -200,7 +200,7 @@ struct mlx5_rsc_debug { void *object; enum dbg_rsc_type type; struct dentry *root; - struct mlx5_field_desc fields[0]; + struct mlx5_field_desc fields[]; }; enum mlx5_dev_event { diff --git a/include/linux/mlx5/mlx5_ifc.h b/include/linux/mlx5/mlx5_ifc.h index 69b27c7dfc3e..c55686ff6504 100644 --- a/include/linux/mlx5/mlx5_ifc.h +++ b/include/linux/mlx5/mlx5_ifc.h @@ -1677,7 +1677,7 @@ struct mlx5_ifc_wq_bits { u8 reserved_at_140[0x4c0]; - struct mlx5_ifc_cmd_pas_bits pas[0]; + struct mlx5_ifc_cmd_pas_bits pas[]; }; struct mlx5_ifc_rq_num_bits { @@ -1895,7 +1895,7 @@ struct mlx5_ifc_resource_dump_menu_segment_bits { u8 reserved_at_20[0x10]; u8 num_of_records[0x10]; - struct mlx5_ifc_resource_dump_menu_record_bits record[0]; + struct mlx5_ifc_resource_dump_menu_record_bits record[]; }; struct mlx5_ifc_resource_dump_resource_segment_bits { @@ -1907,7 +1907,7 @@ struct mlx5_ifc_resource_dump_resource_segment_bits { u8 index2[0x20]; - u8 payload[0][0x20]; + u8 payload[][0x20]; }; struct mlx5_ifc_resource_dump_terminate_segment_bits { @@ -2984,7 +2984,7 @@ struct mlx5_ifc_flow_context_bits { u8 reserved_at_1200[0x600]; - union mlx5_ifc_dest_format_struct_flow_counter_list_auto_bits destination[0]; + union mlx5_ifc_dest_format_struct_flow_counter_list_auto_bits destination[]; }; enum { @@ -3276,7 +3276,7 @@ struct mlx5_ifc_rqtc_bits { u8 reserved_at_e0[0x6a0]; - struct mlx5_ifc_rq_num_bits rq_num[0]; + struct mlx5_ifc_rq_num_bits rq_num[]; }; enum { @@ -3388,7 +3388,7 @@ struct mlx5_ifc_nic_vport_context_bits { u8 reserved_at_7e0[0x20]; - u8 current_uc_mac_address[0][0x40]; + u8 current_uc_mac_address[][0x40]; }; enum { @@ -4310,7 +4310,7 @@ struct mlx5_ifc_query_xrc_srq_out_bits { u8 reserved_at_280[0x600]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_query_xrc_srq_in_bits { @@ -4588,7 +4588,7 @@ struct mlx5_ifc_query_srq_out_bits { u8 reserved_at_280[0x600]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_query_srq_in_bits { @@ -4799,7 +4799,7 @@ struct mlx5_ifc_query_qp_out_bits { u8 reserved_at_800[0x80]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_query_qp_in_bits { @@ -5132,7 +5132,7 @@ struct mlx5_ifc_query_hca_vport_pkey_out_bits { u8 reserved_at_40[0x40]; - struct mlx5_ifc_pkey_bits pkey[0]; + struct mlx5_ifc_pkey_bits pkey[]; }; struct mlx5_ifc_query_hca_vport_pkey_in_bits { @@ -5168,7 +5168,7 @@ struct mlx5_ifc_query_hca_vport_gid_out_bits { u8 gids_num[0x10]; u8 reserved_at_70[0x10]; - struct mlx5_ifc_array128_auto_bits gid[0]; + struct mlx5_ifc_array128_auto_bits gid[]; }; struct mlx5_ifc_query_hca_vport_gid_in_bits { @@ -5436,7 +5436,7 @@ struct mlx5_ifc_query_flow_counter_out_bits { u8 reserved_at_40[0x40]; - struct mlx5_ifc_traffic_counter_bits flow_statistics[0]; + struct mlx5_ifc_traffic_counter_bits flow_statistics[]; }; struct mlx5_ifc_query_flow_counter_in_bits { @@ -5530,7 +5530,7 @@ struct mlx5_ifc_query_eq_out_bits { u8 reserved_at_300[0x580]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_query_eq_in_bits { @@ -5555,7 +5555,7 @@ struct mlx5_ifc_packet_reformat_context_in_bits { u8 reserved_at_20[0x10]; u8 reformat_data[2][0x8]; - u8 more_reformat_data[0][0x8]; + u8 more_reformat_data[][0x8]; }; struct mlx5_ifc_query_packet_reformat_context_out_bits { @@ -5566,7 +5566,7 @@ struct mlx5_ifc_query_packet_reformat_context_out_bits { u8 reserved_at_40[0xa0]; - struct mlx5_ifc_packet_reformat_context_in_bits packet_reformat_context[0]; + struct mlx5_ifc_packet_reformat_context_in_bits packet_reformat_context[]; }; struct mlx5_ifc_query_packet_reformat_context_in_bits { @@ -5805,7 +5805,7 @@ struct mlx5_ifc_query_cq_out_bits { u8 reserved_at_280[0x600]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_query_cq_in_bits { @@ -6412,7 +6412,7 @@ struct mlx5_ifc_modify_cq_in_bits { u8 reserved_at_300[0x580]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_modify_cong_status_out_bits { @@ -6476,7 +6476,7 @@ struct mlx5_ifc_manage_pages_out_bits { u8 reserved_at_60[0x20]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; enum { @@ -6498,7 +6498,7 @@ struct mlx5_ifc_manage_pages_in_bits { u8 input_num_entries[0x20]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_mad_ifc_out_bits { @@ -7453,7 +7453,7 @@ struct mlx5_ifc_create_xrc_srq_in_bits { u8 reserved_at_300[0x580]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_create_tis_out_bits { @@ -7529,7 +7529,7 @@ struct mlx5_ifc_create_srq_in_bits { u8 reserved_at_280[0x600]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_create_sq_out_bits { @@ -7690,7 +7690,7 @@ struct mlx5_ifc_create_qp_in_bits { u8 wq_umem_valid[0x1]; u8 reserved_at_861[0x1f]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_create_psv_out_bits { @@ -7761,7 +7761,7 @@ struct mlx5_ifc_create_mkey_in_bits { u8 reserved_at_320[0x560]; - u8 klm_pas_mtt[0][0x20]; + u8 klm_pas_mtt[][0x20]; }; enum { @@ -7894,7 +7894,7 @@ struct mlx5_ifc_create_eq_in_bits { u8 reserved_at_3c0[0x4c0]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_create_dct_out_bits { @@ -7951,7 +7951,7 @@ struct mlx5_ifc_create_cq_in_bits { u8 cq_umem_valid[0x1]; u8 reserved_at_2e1[0x59f]; - u8 pas[0][0x40]; + u8 pas[][0x40]; }; struct mlx5_ifc_config_int_moderation_out_bits { @@ -8307,7 +8307,7 @@ struct mlx5_ifc_access_register_out_bits { u8 reserved_at_40[0x40]; - u8 register_data[0][0x20]; + u8 register_data[][0x20]; }; enum { @@ -8327,7 +8327,7 @@ struct mlx5_ifc_access_register_in_bits { u8 argument[0x20]; - u8 register_data[0][0x20]; + u8 register_data[][0x20]; }; struct mlx5_ifc_sltp_reg_bits { @@ -9344,7 +9344,7 @@ struct mlx5_ifc_cmd_in_bits { u8 reserved_at_20[0x10]; u8 op_mod[0x10]; - u8 command[0][0x20]; + u8 command[][0x20]; }; struct mlx5_ifc_cmd_if_box_bits { @@ -9638,7 +9638,7 @@ struct mlx5_ifc_mcqi_reg_bits { u8 reserved_at_a0[0x10]; u8 data_size[0x10]; - union mlx5_ifc_mcqi_reg_data_bits data[0]; + union mlx5_ifc_mcqi_reg_data_bits data[]; }; struct mlx5_ifc_mcc_reg_bits { @@ -10200,7 +10200,7 @@ struct mlx5_ifc_umem_bits { u8 num_of_mtt[0x40]; - struct mlx5_ifc_mtt_bits mtt[0]; + struct mlx5_ifc_mtt_bits mtt[]; }; struct mlx5_ifc_uctx_bits { @@ -10325,7 +10325,7 @@ struct mlx5_ifc_mtrc_stdb_bits { u8 reserved_at_4[0x4]; u8 read_size[0x18]; u8 start_offset[0x20]; - u8 string_db_data[0]; + u8 string_db_data[]; }; struct mlx5_ifc_mtrc_ctrl_bits { @@ -10379,7 +10379,7 @@ struct mlx5_ifc_query_esw_functions_out_bits { struct mlx5_ifc_host_params_context_bits host_params_context; u8 reserved_at_280[0x180]; - u8 host_sf_enable[0][0x40]; + u8 host_sf_enable[][0x40]; }; struct mlx5_ifc_sf_partition_bits { @@ -10399,7 +10399,7 @@ struct mlx5_ifc_query_sf_partitions_out_bits { u8 reserved_at_60[0x20]; - struct mlx5_ifc_sf_partition_bits sf_partition[0]; + struct mlx5_ifc_sf_partition_bits sf_partition[]; }; struct mlx5_ifc_query_sf_partitions_in_bits { diff --git a/include/linux/mlx5/qp.h b/include/linux/mlx5/qp.h index ae63b1ae9004..4e684298d1de 100644 --- a/include/linux/mlx5/qp.h +++ b/include/linux/mlx5/qp.h @@ -402,7 +402,7 @@ struct mlx5_wqe_signature_seg { struct mlx5_wqe_inline_seg { __be32 byte_count; - __be32 data[0]; + __be32 data[]; }; enum mlx5_sig_type {