From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [PATCH net] tun, bpf: fix suspicious RCU usage in tun_{attach,detach}_filter
Date: Thu, 31 Mar 2016 14:16:18 +0200
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Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Michal Kubecek <mkubecek@suse.cz>, davem@davemloft.net,
	sasha.levin@oracle.com, jslaby@suse.cz, mst@redhat.com,
	netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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On 03/31/2016 01:59 PM, Eric Dumazet wrote:
> On Thu, 2016-03-31 at 13:35 +0200, Daniel Borkmann wrote:
>
>> +static inline bool sock_owned_externally(const struct sock *sk)
>> +{
>> +	return sk->sk_flags & (1UL << SOCK_EXTERNAL_OWNER);
>> +}
>> +
>
> Have you reinvented sock_flag(sl, SOCK_EXTERNAL_OWNER) ? ;)
>
> Anyway, using a flag for this purpose sounds overkill to me.

Right.

> Setting it is a way to 'fool' lockdep anyway...

Yep, correct, we'd be fooling the tun case, so this diff doesn't
really make it any better there.

Thanks,
Daniel