From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net: loopback: fix a dst refcounting issue
Date: Sun, 27 Jan 2013 19:26:38 -0500 (EST)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sun, 27 Jan 2013 09:25:08 -0800

> On Sun, 2013-01-27 at 01:32 -0500, David Miller wrote:
> 
>> Applied, I suspect we need to tree wide audit for other instances of
>> this situation.  Probably greps for skb_orphan() would be a good
>> start.
> 
> I highly suspect macvlan needs a skb_dst_drop(), but couldnt trigger
> a case to trigger the fault.

I completely agree, when we hit the ->forward() or ->receive() method
we are leaving the RCU safety zone for the cached dst.

Even if you can't trigger it, this seems clear enough to me that we
should put those skb_dst_drop() calls in, so please formally submit
that patch you posted for Ben as an RFC last week.

Thanks.