Re: [PATCH bpf v3 0/2] bpf: Fix socket leaks around connect(AF_UNSPEC)+listen()

[Kuniyuki Iwashima]

On Wed, Sep 2, 2026 at 4:04 PM Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> wrote:
>
> On Wed, Sep 2, 2026 at 3:52 PM Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
> >
> > On Wed, 2 Sep 2026 11:58:49 -0700 Kuniyuki Iwashima wrote:
> > > > Several BPF socket helpers acquire a socket reference only when
> > > > sk_is_refcounted() == true, and release it, independently, by
> > > > re-evaluating sk_is_refcounted() again at the time the release runs. TCP
> > > > connect(AF_UNSPEC)+listen() sets SOCK_RCU_FREE on an established socket.
> > >
> > > Due to several bug reports, we are now inclined to forbid the
> > > buggy transformation.
> > > https://lore.kernel.org/netdev/CANn89i+px52TtJy3S9=uHxGj3s-WueguRo1Z_4FxO=02KLmwmQ@xxxxxxxxxxxxxx/
> >
> > Kuniyuki, would you be willing to send a patch to do that?
> > Not sure if anyone else is planning to, I wasn't..
>
> Sure, I'll post one like this with s/synchronize_rcu()/-EINVAL/g
> https://lore.kernel.org/netdev/20260804015349.2353056-1-kuniyu@xxxxxxxxxx/

and cover IPV6_ADDRFORM.