Re: [PATCH net v3 2/2] sctp: close UDP tunnel sockets during netns teardown

On Tue, Jul 14, 2026 at 9:51=E2=80=AFPM Ren Wei <[email protected]> wrote:
>
> From: Zhiling Zou <[email protected]>
>
> proc_sctp_do_udp_port() starts per-net SCTP UDP tunneling sockets when
> net.sctp.udp_port is set, and stops/restarts them when the sysctl value
> changes. The netns exit path does not stop these sockets, so a namespace
> can be torn down while its SCTP UDP tunnel sockets are still installed.
>
> Close the UDP tunnel sockets from sctp_ctrlsock_exit() after unregisterin=
g
> the per-net sysctl table. This prevents new sysctl writes from racing in
> while the sockets are being released, and closes the sockets before the
> control socket is destroyed.
>
> Fixes: 046c052b475e ("sctp: enable udp tunneling socks")
> Cc: [email protected]
> Reported-by: Sashiko <[email protected]>
> Closes: https://sashiko.dev/#/patchset/b9f1f02b0780ad6a719e2413f5f0bb8eb7=
702d94.1782585631.git.roxy520tt%40gmail.com
> Signed-off-by: Zhiling Zou <[email protected]>
> Signed-off-by: Ren Wei <[email protected]>
> ---
> Changes in v3:
> - No code changes.
>
>  net/sctp/protocol.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
> index 49d9740b1e0f..27c26e12f95d 100644
> --- a/net/sctp/protocol.c
> +++ b/net/sctp/protocol.c
> @@ -1460,6 +1460,7 @@ static int __net_init sctp_ctrlsock_init(struct net=
 *net)
>  static void __net_exit sctp_ctrlsock_exit(struct net *net)
>  {
>         sctp_sysctl_net_unregister(net);
> +       sctp_udp_sock_stop(net);
>
>         /* Free the control endpoint.  */
>         inet_ctl_sock_destroy(net->sctp.ctl_sock);
> --
> 2.43.0
>
Acked-by: Xin Long <[email protected]>