From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9F55C4321D for ; Mon, 20 Aug 2018 12:59:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7C57D206B5 for ; Mon, 20 Aug 2018 12:59:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7C57D206B5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ACULAB.COM Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726735AbeHTQPL convert rfc822-to-8bit (ORCPT ); Mon, 20 Aug 2018 12:15:11 -0400 Received: from eu-smtp-delivery-211.mimecast.com ([146.101.78.211]:38598 "EHLO eu-smtp-delivery-211.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726481AbeHTQPK (ORCPT ); Mon, 20 Aug 2018 12:15:10 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by eu-smtp-1.mimecast.com with ESMTP id uk-mta-63-psq3Hum6Nf-CiGHl1SCeGw-1; Mon, 20 Aug 2018 13:59:34 +0100 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b::d117) by AcuMS.aculab.com (fd9f:af1c:a25b::d117) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 20 Aug 2018 14:01:13 +0100 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Mon, 20 Aug 2018 14:01:13 +0100 From: David Laight To: 'Chuanhua Han' , "broonie@kernel.org" , "boris.brezillon@bootlin.com" CC: "linux-spi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , "jiafei.pan@nxp.com" , "zhiqiang.hou@nxp.com" Subject: RE: [PATCH] mtd: m25p80: consider max message size when use the spi_mem_xx() API Thread-Topic: [PATCH] mtd: m25p80: consider max message size when use the spi_mem_xx() API Thread-Index: AQHUOIO1v0mwy7J+K0+V94NCbAoDI6TImGqw Date: Mon, 20 Aug 2018 13:01:13 +0000 Message-ID: <109aeb2622924f20b29743746bb77ce2@AcuMS.aculab.com> References: <1534769013-43449-1-git-send-email-chuanhua.han@nxp.com> In-Reply-To: <1534769013-43449-1-git-send-email-chuanhua.han@nxp.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.33] MIME-Version: 1.0 X-MC-Unique: psq3Hum6Nf-CiGHl1SCeGw-1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chuanhua Han > Sent: 20 August 2018 13:44 > > Signed-off-by: Chuanhua Han > --- > Changes in v3: > Rename variable name "val" to "opcode_addr_dummy_sum". > Place the legitimacy of the transfer size(i.e., "pi_max_message_size(mem->spi)" and > "opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr-> mem_ops->exec_op) {" > structure and add "spi_max_transfer_size(mem->spi) and opcode_addr_dummy_sum". > Adjust the formatting alignment of your code. > "(unsigned long)op->data.nbytes" was modified to "(unsigned long)(op->data.nbytes)". > > Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI memory controllers") > --- > drivers/spi/spi-mem.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c > index 990770d..5ec2bc9 100644 > --- a/drivers/spi/spi-mem.c > +++ b/drivers/spi/spi-mem.c > @@ -328,10 +328,24 @@ EXPORT_SYMBOL_GPL(spi_mem_exec_op); > int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op) > { > struct spi_controller *ctlr = mem->spi->controller; > + unsigned long opcode_addr_dummy_sum = sizeof(op->cmd.opcode) + > + op->addr.nbytes + > + op->dummy.nbytes; I'd split that (and shorten the variable name) to avoid line wrap. Maybe: unsigned long len; len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes; > > if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size) > return ctlr->mem_ops->adjust_op_size(mem, op); > > + if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) { > + if (spi_max_message_size(mem->spi) < opcode_addr_dummy_sum || > + spi_max_transfer_size(mem->spi) < opcode_addr_dummy_sum) > + return -EINVAL; Those comparisons are lexically backwards, you want 'value op constant'. So: if (len > spi_max_message_size(mem->spi) || len > spi_max_transfer_size(mem->spi)) return -EINVAL. Although I'm surprised you need to do both comparisons. > + > + op->data.nbytes = min3((unsigned long)(op->data.nbytes), > + spi_max_transfer_size(mem->spi), > + spi_max_message_size(mem->spi) - > + opcode_addr_dummy_sum); That looks like a strange limit... > + } > + > return 0; > } > EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size); > -- > 2.7.4 David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)