On 2019/1/31 2:10, David Miller wrote:
> From: YueHaibing <yuehaib...@huawei.com>
> Date: Wed, 30 Jan 2019 18:19:02 +0800
>
>> There is a potential NULL pointer dereference in case
>> kzalloc() fails and returns NULL.
>>
>> Fixes: 69f52adb2d53 ("mISDN: Add HFC USB driver")
>> Signed-off-by: YueHaibing <yuehaib...@huawei.com>
>> ---
>> drivers/isdn/hardware/mISDN/hfcsusb.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/isdn/hardware/mISDN/hfcsusb.c
>> b/drivers/isdn/hardware/mISDN/hfcsusb.c
>> index 124ff53..5660d5a 100644
>> --- a/drivers/isdn/hardware/mISDN/hfcsusb.c
>> +++ b/drivers/isdn/hardware/mISDN/hfcsusb.c
>> @@ -263,6 +263,8 @@ hfcsusb_ph_info(struct hfcsusb *hw)
>> int i;
>>
>> phi = kzalloc(struct_size(phi, bch, dch->dev.nrbchan), GFP_ATOMIC);
>> + if (!phi)
>> + return;
>
> If we fail with an error and do not perform the operation we were requested to
> make, we must return an error to the caller, and the caller must do something
> reasonable with that error (perhaps return it to it's caller) and so on and
> so forth.
hfcsusb_ph_info alloced the 'phi'，then use it _alloc_mISDN_skb in _queue_data.
while _alloc_mISDN_skb fails, it also just return without err handling,then
kfree(phi).
It seems that all the caller of hfcsusb_ph_info doesn't care the return value.
>
> .
>
