From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCHv3 net 0/2] net: fixes for device unregistration
Date: Fri, 10 Jul 2015 18:17:30 -0700 (PDT)
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From: Julian Anastasov <ja@ssi.bg>
Date: Thu,  9 Jul 2015 09:59:08 +0300

> Test script from Eric W. Biederman can catch a problem
> where packets from backlog are processed long after the last
> synchronize_net call. This can be reproduced after few tests
> if commit 381c759d9916 ("ipv4: Avoid crashing in ip_error")
> is reverted for the test. Incoming packets do not hold
> reference to device but even if they do, subsystems do not
> expect packets to fly during and after the NETDEV_UNREGISTER
> event.
> 
> The first fix has the cost of netif_running check in fast path.
> The second fix calls rcu_read_lock while local IRQ is disabled,
> I hope this is not against the rules.

Thanks for fixing this tricky bug.

Applied and queued up for -stable.