netdev - Re: mptcp splat

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAADnVQJxsqbJgu9K-ML2-1tRcgEmHY-UuQOCDxqv8_6iVkW7Tg@mail.gmail.com>
Date: Fri, 29 Mar 2024 09:26:11 -0700
From: Alexei Starovoitov <alexei.starovoitov@...il.com>
To: Matthieu Baerts <matttbe@...nel.org>
Cc: Martin KaFai Lau <martin.lau@...ux.dev>, Paolo Abeni <pabeni@...hat.com>, 
	Network Development <netdev@...r.kernel.org>, bpf <bpf@...r.kernel.org>, 
	MPTCP Upstream <mptcp@...ts.linux.dev>, Mat Martineau <martineau@...nel.org>, 
	Jakub Kicinski <kuba@...nel.org>, Martin KaFai Lau <martin.lau@...nel.org>, 
	Geliang Tang <geliang@...nel.org>
Subject: Re: mptcp splat

On Thu, Mar 28, 2024 at 10:35 AM Matthieu Baerts <matttbe@...nel.org> wrote:
>
> Hi Martin,
>
> On 27/03/2024 23:16, Martin KaFai Lau wrote:
>
> (...)
>
> > Unrelated, is there a way to tell if a tcp_sock is a subflow?
>
> Yes, you can use "sk_is_mptcp(sk)". Please note that this 'sk' *has* to
> be a tcp_sock, this is not checked by the helper.
>
> That's what is used with bpf_mptcp_sock_from_subflow()
>
> https://elixir.bootlin.com/linux/latest/source/net/mptcp/bpf.c#L15
>
> > bpf prog
> > can use it to decide if it wants to setsockopt on a subflow or not.
> I think it is important to keep the possibility to set socket options
> per subflow. If the original issue discussed here is limited to
> set_rcvlowat(), best to address it there.


All makes sense to me.

Paolo,
could you send an official patch?