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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 F3CF7ECE562 for ; Mon, 17 Sep 2018 03:57:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 48E13206B8 for ; Mon, 17 Sep 2018 03:57:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 48E13206B8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.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 S1728169AbeIQJXS (ORCPT ); Mon, 17 Sep 2018 05:23:18 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:48203 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726169AbeIQJXR (ORCPT ); Mon, 17 Sep 2018 05:23:17 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 73BD6E6167771; Mon, 17 Sep 2018 11:57:44 +0800 (CST) Received: from [127.0.0.1] (10.177.31.96) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.399.0; Mon, 17 Sep 2018 11:57:41 +0800 Subject: Re: [PATCH net-next] net/smc: cast sizeof to int for comparison To: Andreas Schwab References: <20180915100036.20100-1-yuehaibing@huawei.com> <87zhwj6liz.fsf@igel.home> CC: , , , , From: YueHaibing Message-ID: Date: Mon, 17 Sep 2018 11:57:40 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <87zhwj6liz.fsf@igel.home> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.31.96] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018/9/15 19:35, Andreas Schwab wrote: > On Sep 15 2018, YueHaibing wrote: > >> Comparing an int to a size, which is unsigned, causes the int to become >> unsigned, giving the wrong result. kernel_sendmsg can return a negative >> error code. >> >> Signed-off-by: YueHaibing >> --- >> net/smc/smc_clc.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c >> index 83aba9a..fd0f5ce 100644 >> --- a/net/smc/smc_clc.c >> +++ b/net/smc/smc_clc.c >> @@ -446,7 +446,7 @@ int smc_clc_send_proposal(struct smc_sock *smc, int smc_type, >> vec[i++].iov_len = sizeof(trl); >> /* due to the few bytes needed for clc-handshake this cannot block */ >> len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen); >> - if (len < sizeof(pclc)) { >> + if (len < (int)sizeof(pclc)) { >> if (len >= 0) { >> reason_code = -ENETUNREACH; >> smc->sk.sk_err = -reason_code; > > It would perhaps be better to handle len < 0 first. That need refactor the err hangding, is worth doing it? > > Andreas. >