Re: [PATCH v2 mptcp-net 2/2] mptcp: fix duplicate reset on fastclose

[Geliang Tang <geliang@kernel.org>]

On Tue, 2025-11-11 at 08:27 +0100, Paolo Abeni wrote:
> On 11/11/25 7:14 AM, Matthieu Baerts wrote:
> > 11 Nov 2025 02:59:28 Geliang Tang <geliang@kernel.org>:
> > > On Fri, 2025-11-07 at 08:23 +0100, Paolo Abeni wrote:
> > > > @@ -2448,7 +2447,7 @@ static void
> > > > __mptcp_subflow_disconnect(struct
> > > > sock *ssk,
> > > >                        unsigned int flags)
> > > 
> > > nit:
> > > 
> > > The 3rd argument "flags" of __mptcp_subflow_disconnect is useless
> > > now.
> > > We can drop it.
> > 
> > I don't think it is useless: __mptcp_close_ssk() is still called
> > with either
> > the push flag or no flag (0).
> > 
> > Because this patch is for net, we should avoid unnecessary
> > modifications:
> > we should not change the type or the name of the function argument
> > for
> > "cosmetic" reasons.
> 
> FWIW, I agree with Mat.

I agree too. Let's apply it as is.

Thanks,
-Geliang

> 
> > > > @@ -2511,20 +2510,13 @@ static void __mptcp_close_ssk(struct
> > > > sock
> > > > *sk, struct sock *ssk,
> > > >     if (dispose_it)
> > > >         list_del(&subflow->node);
> > > >  
> > > > -   if ((flags & MPTCP_CF_FASTCLOSE) &&
> > > > !__mptcp_check_fallback(msk)) {
> > > > -       /* be sure to force the tcp_close path
> > > > -        * to generate the egress reset
> > > > -        */
> > > > -       ssk->sk_lingertime = 0;
> > > > -       sock_set_flag(ssk, SOCK_LINGER);
> > > > -       subflow->send_fastclose = 1;
> > > > -   }
> > > > +   if (subflow->send_fastclose && ssk->sk_state != TCP_CLOSE)
> > > > +       tcp_set_state(ssk, TCP_CLOSE);
> > > >  
> > > >     need_push = (flags & MPTCP_CF_PUSH) &&
> > > > __mptcp_retransmit_pending_data(sk);
> > > >     if (!dispose_it) {
> > > >         __mptcp_subflow_disconnect(ssk, subflow, flags);
> > > >         release_sock(ssk);
> > > > -
> > 
> > (This line should not be removed but this can be fixed when
> > applying the patch.)
> 
> Thanks!
> 
> /P
>