From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758825AbcAMLch (ORCPT ); Wed, 13 Jan 2016 06:32:37 -0500 Received: from szxga02-in.huawei.com ([119.145.14.65]:52925 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757235AbcAMLcg (ORCPT ); Wed, 13 Jan 2016 06:32:36 -0500 Message-ID: <569635AF.4070204@huawei.com> Date: Wed, 13 Jan 2016 19:31:59 +0800 From: Weidong Wang User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Felix Fietkau CC: Paolo Abeni , David Miller , , , Joe Perches , , , Subject: Re: bgmac: fix a missing check for build_skb References: <5695BF41.2040002@huawei.com> <1452674087.4516.3.camel@redhat.com> <5696262D.3040803@huawei.com> <56962DAF.9040807@openwrt.org> In-Reply-To: <56962DAF.9040807@openwrt.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.21.100] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020202.569635C0.0048,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 88a68df9e24714b045eb57012bd2aef9 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2016/1/13 18:57, Felix Fietkau wrote: > On 2016-01-13 11:25, Weidong Wang wrote: >> On 2016/1/13 16:34, Paolo Abeni wrote: >>> On Wed, 2016-01-13 at 11:06 +0800, Weidong Wang wrote: >>>> when build_skb failed, it may occure a NULL pointer. >>>> So add a 'NULL check' for it. >>>> >>>> Signed-off-by: Weidong Wang >>>> --- >>>> drivers/net/ethernet/broadcom/bgmac.c | 5 +++++ >>>> 1 file changed, 5 insertions(+) >>>> >>>> diff --git a/drivers/net/ethernet/broadcom/bgmac.c b/drivers/net/ethernet/broadcom/bgmac.c >>>> index 21e3c38..d75180a 100644 >>>> --- a/drivers/net/ethernet/broadcom/bgmac.c >>>> +++ b/drivers/net/ethernet/broadcom/bgmac.c >>>> @@ -466,6 +466,11 @@ static int bgmac_dma_rx_read(struct bgmac *bgmac, struct bgmac_dma_ring *ring, >>>> len -= ETH_FCS_LEN; >>>> >>>> skb = build_skb(buf, BGMAC_RX_ALLOC_SIZE); >>>> + if (unlikely(skb)) { >>> >>> Should that be instead: >>> >>> if (unlikely(!skb)) { >>> >>> ? >>> >> >> What to instead of it? > Your patch has a logic error (missing the !), and it's breaking the > ethernet driver completely instead of fixing anything. > Did you even test this? > Yep, you are right. Sorry for that. I just review the source code without any test. I should resent it again. > Dave, why did you apply this patch so fast without any chance of review? > > - Felix > > . > Regards, Weidong