From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B05821DFF3; Mon, 22 Jan 2024 10:31:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705919468; cv=none; b=O9gSOp8Bpxl56woXLbsBUV+Oh0zvsjnZGk0eqClIXy9T/KL8NYV+p2rJuAJuQ/Lg1AWEVLFMw6F5Exbj6ASOavF2VwjrDqQW+coKwQhTbPQlRHjtqLkXkDg5iKD17AnKE0Ssydhg5XCI7eZQsihk/zV9rJBYbiD8XRcNK/BT5tY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705919468; c=relaxed/simple; bh=Adk4o/syB8kwb6hMdHdd8CxVfC3VENFja8OPDajgNt8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hMW/rcA1rWoxzNrt1smP4YO5GJu7aMmVEdoFjeykTygwCLT0sLMus8Ibu5pdwmeR7hDuzD1QUz2aFmdUdvNnNkRYVbkuDeNA254tQyXNQHurI811NnEZKJRepV+aVxGBtq/fO3Gw12oKjHzcCG697W5vDeJ+K+IaibCZj5ph1ts= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VXYiQi5z; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VXYiQi5z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F258C43390; Mon, 22 Jan 2024 10:31:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705919468; bh=Adk4o/syB8kwb6hMdHdd8CxVfC3VENFja8OPDajgNt8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VXYiQi5zdrm6D/arV+leoLROlbr7Rb91J3KkdLkhJFacvol55XCXpGBRHkReoQ+wS MkW8a9h0UGD2duiJuDVOIRQc078qQhCdjKiWa7YZ0JajQZT3g7KahEljOb9k9u4+L0 SarFw28EbOctK+w9oDuislDN8TCphzc4XCNBhJM2xZHh4GJsXbOdYpiurVhYnFUbSZ hDzRTkr8ZuZ39SzKyQg1H82b1R5/uANddhFrvfCs4Uxxn1eX18NofmN0nwOXZi936R 6fNa0KMEOiAcpeAHyHYvOfNhPE6/J+R7WSebFfcC47s9rnezA6PZInjFYR6EvpMXUq c/Nbd7OHGXp9g== Date: Mon, 22 Jan 2024 10:31:00 +0000 From: Simon Horman To: Danielle Ratson Cc: netdev@vger.kernel.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, corbet@lwn.net, linux@armlinux.org.uk, sdf@google.com, kory.maincent@bootlin.com, maxime.chevallier@bootlin.com, vladimir.oltean@nxp.com, przemyslaw.kitszel@intel.com, ahmed.zaki@intel.com, richardcochran@gmail.com, shayagr@amazon.com, paul.greenwalt@intel.com, jiri@resnulli.us, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, mlxsw@nvidia.com, petrm@nvidia.com, idosch@nvidia.com Subject: Re: [RFC PATCH net-next 7/9] ethtool: cmis_cdb: Add a layer for supporting CDB commands Message-ID: <20240122103100.GA126470@kernel.org> References: <20240122084530.32451-1-danieller@nvidia.com> <20240122084530.32451-8-danieller@nvidia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240122084530.32451-8-danieller@nvidia.com> On Mon, Jan 22, 2024 at 10:45:28AM +0200, Danielle Ratson wrote: ... > +/** > + * struct ethtool_cmis_cdb_request - CDB commands request fields as decribed in > + * the CMIS standard > + * @id: Command ID. > + * @epl_len: EPL memory length. > + * @lpl_len: LPL memory length. > + * @chk_code: Check code for the previous field and the payload. > + * @resv1: Added to match the CMIS standard request continuity. > + * @resv2: Added to match the CMIS standard request continuity. > + * @payload: Payload for the CDB commands. > + */ > +struct ethtool_cmis_cdb_request { > + __be16 id; > + struct_group(body, > + u16 epl_len; > + u8 lpl_len; > + u8 chk_code; > + u8 resv1; > + u8 resv2; > + u8 payload[ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH]; > + ); > +}; > + > +#define CDB_F_COMPLETION_VALID BIT(0) > +#define CDB_F_STATUS_VALID BIT(1) > + > +/** > + * struct ethtool_cmis_cdb_cmd_args - CDB commands execution arguments > + * @req: CDB command fields as described in the CMIS standard. > + * @max_duration: Maximum duration time for command completion in msec. > + * @read_write_len_ext: Allowable additional number of byte octets to the LPL > + * in a READ or a WRITE commands. > + * @rpl_exp_len: Expected reply length in bytes. > + * @flags: Validation flags for CDB commands. > + */ > +struct ethtool_cmis_cdb_cmd_args { > + struct ethtool_cmis_cdb_request req; > + u16 max_duration; > + u8 read_write_len_ext; > + u8 rpl_exp_len; > + u8 flags; > +}; ... > +int ethtool_cmis_page_init(struct ethtool_module_eeprom *page_data, > + u8 page, u32 offset, u32 length) > +{ > + page_data->page = page; > + page_data->offset = offset; > + page_data->length = length; > + page_data->i2c_address = ETHTOOL_CMIS_CDB_PAGE_I2C_ADDR; > + page_data->data = kmalloc(page_data->length, GFP_KERNEL); > + if (!page_data->data) > + return -ENOMEM; > + > + return 0; > +} ... > +static int > +__ethtool_cmis_cdb_execute_cmd(struct net_device *dev, > + struct ethtool_module_eeprom *page_data, > + u32 offset, u32 length, void *data) > +{ > + const struct ethtool_ops *ops = dev->ethtool_ops; > + struct netlink_ext_ack extack = {}; > + int err; > + > + page_data->offset = offset; > + page_data->length = length; > + > + memset(page_data->data, 0, ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH); > + memcpy(page_data->data, data, page_data->length); > + > + err = ops->set_module_eeprom_by_page(dev, page_data, &extack); > + if (err < 0) { > + if (extack._msg) > + netdev_err(dev, "%s\n", extack._msg); > + } > + > + return err; > +} ... > +int ethtool_cmis_cdb_execute_cmd(struct net_device *dev, > + struct ethtool_cmis_cdb_cmd_args *args) > +{ > + struct ethtool_module_eeprom page_data = {}; > + u32 offset; > + int err; > + > + args->req.chk_code = > + cmis_cdb_calc_checksum(&args->req, sizeof(args->req)); > + > + if (args->req.lpl_len > args->read_write_len_ext) { > + ethnl_module_fw_flash_ntf_err(dev, > + "LPL length is longer than CDB read write length extension allows"); > + return -EINVAL; > + } > + > + err = ethtool_cmis_page_init(&page_data, ETHTOOL_CMIS_CDB_CMD_PAGE, 0, > + ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH); ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH is passed as the length argument of ethtool_cmis_page_init, which will allocate that many bytes for page_data->data. > + if (err < 0) > + return err; > + > + /* According to the CMIS standard, there are two options to trigger the > + * CDB commands. The default option is triggering the command by writing > + * the CMDID bytes. Therefore, the command will be split to 2 calls: > + * First, with everything except the CMDID field and then the CMDID > + * field. > + */ > + offset = CMIS_CDB_CMD_ID_OFFSET + > + offsetof(struct ethtool_cmis_cdb_request, body); > + err = __ethtool_cmis_cdb_execute_cmd(dev, &page_data, offset, > + sizeof(args->req.body), > + &args->req.body); Hi Danielle, However, here sizeof(args->req.body) is passed as the length argument of __ethtool_cmis_cdb_execute_cmd() which will: 1. Zero ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH bytes of page_data->data 2. Copy sizeof(args->req.body) bytes into page_data->data args->req.body includes several fields, one of which is ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH bytes long. So, args->req.body > ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH and it seems that step 2 above causes a buffer overrun. Flagged by clang-17 W=1 build In file included from net/ethtool/cmis_cdb.c:3: In file included from ./include/linux/ethtool.h:16: In file included from ./include/linux/bitmap.h:12: In file included from ./include/linux/string.h:295: ./include/linux/fortify-string.h:579:4: error: call to '__write_overflow_field' declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning] 579 | __write_overflow_field(p_size_field, size); | ^ ./include/linux/fortify-string.h:579:4: error: call to '__write_overflow_field' declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning] ./include/linux/fortify-string.h:579:4: error: call to '__write_overflow_field' declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning] > + if (err < 0) > + goto out; > + > + offset = CMIS_CDB_CMD_ID_OFFSET + > + offsetof(struct ethtool_cmis_cdb_request, id); > + err = __ethtool_cmis_cdb_execute_cmd(dev, &page_data, offset, > + sizeof(args->req.id), > + &args->req.id); > + if (err < 0) > + goto out; > + > + err = cmis_cdb_wait_for_completion(dev, args); > + if (err < 0) > + goto out; > + > + err = cmis_cdb_wait_for_status(dev, args); > + if (err < 0) > + goto out; > + > + err = cmis_cdb_process_reply(dev, &page_data, args); > + > +out: > + ethtool_cmis_page_fini(&page_data); > + return err; > +} ...