Re: [PATCH net] sctp: fix missing encap_port propagation for GSO fragments

Marcelo Ricardo Leitner
2026-04-13T12:37:14Z

On Sun, Apr 12, 2026 at 02:13:51PM -0400, Xin Long wrote:
> encap_port in SCTP_INPUT_CB(skb) is used by sctp_vtag_verify() for
> SCTP-over-UDP processing. In the GSO case, it is only set on the head
> skb, while fragment skbs leave it 0.
>
> This results in fragment skbs seeing encap_port == 0, breaking
> SCTP-over-UDP connections.
>
> Fix it by propagating encap_port from the head skb cb when initializing
> fragment skbs in sctp_inq_pop().
>
> Fixes: 046c052b475e ("sctp: enable udp tunneling socks")
> Signed-off-by: Xin Long <lucien.xin@gmail.com>

Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>