Re: [PATCH net] tun, bpf: fix suspicious RCU usage in tun_{attach,detach}_filter
From: Daniel Borkmann <daniel@iogearbox.net>
Date: 2016-03-31 21:53:08
From: Daniel Borkmann <daniel@iogearbox.net>
Date: 2016-03-31 21:53:08
On 03/31/2016 09:48 PM, Hannes Frederic Sowa wrote: [...]
Tightest solution would probably be to combine both patches. bool called_by_tuntap; old_fp = rcu_dereference_protected(sk->sk_filter, called_by_tuntap ? lockdep_rtnl_is_held() : lockdep_sock_is_held());
If I understand you correctly with combining them, you mean you'd still need the API change to pass the bool 'called_by_tuntap' down, right? If so, your main difference is, after all, to replace the sock_owned_by_user() with the lockdep_sock_is_held() construction instead, correct? But then, isn't it already sufficient when you pass the bool itself down that 'demuxes' in this case between the sock_owned_by_user() vs lockdep_rtnl_is_held() check? Thanks, Daniel