From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [patch] hamradio: avoid null deref
Date: Wed, 23 Dec 2009 13:32:36 -0800 (PST)
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From: Jarek Poplawski <jarkao2@gmail.com>
Date: Wed, 23 Dec 2009 18:47:46 +0100

> Dan Carpenter wrote, On 12/23/2009 02:25 PM:
> 
>> If dev == NULL we shouldn't dereference it.
>> 
>> Signed-off-by: Dan Carpenter <error27@gmail.com>
>> 
>> --- orig/drivers/net/hamradio/bpqether.c	2009-12-22 23:58:56.000000000 +0200
>> +++ devel/drivers/net/hamradio/bpqether.c	2009-12-22 23:59:46.000000000 +0200
>> @@ -283,7 +283,6 @@ static netdev_tx_t bpq_xmit(struct sk_bu
>>  	bpq = netdev_priv(dev);
>>  
>>  	if ((dev = bpq_get_ether_dev(dev)) == NULL) {
>> -		dev->stats.tx_dropped++;
> 
> Why not use a separate variable for another dev? This stat
> should be helpful for debugging.

And that is definitely the intent of the code here, to
bump the statistic in the original device object.