From: Weidong Wang <wangweidong1@huawei.com>
Subject: Re: bgmac: fix a missing check for build_skb
Date: Wed, 13 Jan 2016 18:25:49 +0800
Message-ID: <5696262D.3040803@huawei.com>
References: <5695BF41.2040002@huawei.com> <1452674087.4516.3.camel@redhat.com>
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Cc: David Miller <davem@davemloft.net>, <nbd@openwrt.org>,
	<zajec5@gmail.com>, <hauke@hauke-m.de>,
	Joe Perches <joe@perches.com>, <peter.senna@gmail.com>,
	<netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>
To: Paolo Abeni <pabeni@redhat.com>
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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 <wangweidong1@huawei.com>
>> ---
>>  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?

Regards,
Weidong

>> +				bgmac_err(bgmac, "build_skb failed\n");
>> +				put_page(virt_to_head_page(buf));
>> +				break;
>> +			}
>>  			skb_put(skb, BGMAC_RX_FRAME_OFFSET +
>>  				BGMAC_RX_BUF_OFFSET + len);
>>  			skb_pull(skb, BGMAC_RX_FRAME_OFFSET +
> 
> 
> .
>