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Message-ID: <61130a41-a626-c860-e321-9295f9c9d0dd@meizu.com>
Date:   Mon, 30 May 2022 16:22:11 +0800
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Subject: Re: [PATCH] staging: rtl8712: Fix pointer dereferenced before
 checking
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC:     Larry Finger <Larry.Finger@lwfinger.net>,
        Florian Schilhabel <florian.c.schilhabel@googlemail.com>,
        <linux-staging@lists.linux.dev>, <linux-kernel@vger.kernel.org>
References: <1653897933-25931-1-git-send-email-baihaowen@meizu.com>
 <YpR85JgzGsTzYm3W@kroah.com>
From:   baihaowen <baihaowen@meizu.com>
In-Reply-To: <YpR85JgzGsTzYm3W@kroah.com>
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在 2022/5/30 下午4:14, Greg Kroah-Hartman 写道:
> On Mon, May 30, 2022 at 04:05:32PM +0800, Haowen Bai wrote:
>> The padapter->recvpriv.signal_qual_data is dereferencing before null
>> checking, so move it after checking.
>>
>> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
>> ---
>>  drivers/staging/rtl8712/rtl8712_recv.c | 4 +++-
>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/staging/rtl8712/rtl8712_recv.c b/drivers/staging/rtl8712/rtl8712_recv.c
>> index 7f1fdd058551..8ed94b259dbe 100644
>> --- a/drivers/staging/rtl8712/rtl8712_recv.c
>> +++ b/drivers/staging/rtl8712/rtl8712_recv.c
>> @@ -863,10 +863,12 @@ static void process_link_qual(struct _adapter *padapter,
>>  {
>>  	u32	last_evm = 0, tmpVal;
>>  	struct rx_pkt_attrib *pattrib;
>> -	struct smooth_rssi_data *sqd = &padapter->recvpriv.signal_qual_data;
>> +	struct smooth_rssi_data *sqd;
>>  
>>  	if (!prframe || !padapter)
>>  		return;
>> +
>> +	sqd = &padapter->recvpriv.signal_qual_data;
> How can padapter ever be NULL in this codepath?
>
> thanks,
>
> greg k-h
Just the original  code, show me

if (!prframe || !padapter)

It would be null, and then return.

-- 
Haowen Bai