From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [Patch net-next] ipv6: fix a potential NULL deref
Date: Mon, 29 Oct 2012 13:22:03 -0400 (EDT)
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From: Cong Wang <amwang@redhat.com>
Date: Mon, 29 Oct 2012 14:49:26 +0800

> On Mon, 2012-10-29 at 07:10 +0100, Eric Dumazet wrote:
>> > -		dst_release(&rt->dst);
>> > +		if (rt)
>> > +			dst_release(&rt->dst);
>> >  	}
>> >  
>> 
>> dst_release() is like kfree(), it accepts a NULL argument.
>> 
> 
> 'rt->dst' already dereferences 'rt', no matter dst_release() accepts
> NULL or not.

It's taking the address of a struct member, it's not a dereference.

You know what the difference is right?