From mboxrd@z Thu Jan 1 00:00:00 1970 From: YueHaibing Subject: Re: [PATCH net-next] net/smc: cast sizeof to int for comparison Date: Mon, 17 Sep 2018 11:57:40 +0800 Message-ID: References: <20180915100036.20100-1-yuehaibing@huawei.com> <87zhwj6liz.fsf@igel.home> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: , , , , To: Andreas Schwab Return-path: In-Reply-To: <87zhwj6liz.fsf@igel.home> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.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. >