Re: bgmac: fix a missing check for build_skb

From: Weidong Wang
Date: Wed Jan 13 2016 - 06:32:40 EST


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 <wangweidong1@xxxxxxxxxx>
>>>> ---
>>>> 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