On Sun, Nov 18, 2018 at 04:14:47PM +0800, Xin Long wrote:
> This reverts commit 22d7be267eaa8114dcc28d66c1c347f667d7878a.
>
> The dst's mtu in transport can be updated by a non sctp place like
> in xfrm where the MTU information didn't get synced between asoc,
> transport and dst, so it is still needed to do the pmtu check
> in sctp_packet_config.
> ---
> include/net/sctp/sctp.h | 12 ++++++++++++
> net/sctp/output.c | 3 +++
> 2 files changed, 15 insertions(+)
>
> diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
> index 8c2caa3..ab9242e 100644
> --- a/include/net/sctp/sctp.h
> +++ b/include/net/sctp/sctp.h
> @@ -608,4 +608,16 @@ static inline __u32 sctp_dst_mtu(const struct dst_entry *dst)
> SCTP_DEFAULT_MINSEGMENT));
> }
>
> +static inline bool sctp_transport_pmtu_check(struct sctp_transport *t)
> +{
> + __u32 pmtu = sctp_dst_mtu(t->dst);
> +
> + if (t->pathmtu == pmtu)
> + return true;
> +
> + t->pathmtu = pmtu;
> +
> + return false;
> +}
> +
> #endif /* __net_sctp_h__ */
> diff --git a/net/sctp/output.c b/net/sctp/output.c
> index 67939ad..0860122 100644
> --- a/net/sctp/output.c
> +++ b/net/sctp/output.c
> @@ -118,6 +118,9 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag,
> sctp_transport_route(tp, NULL, sp);
> if (asoc->param_flags & SPP_PMTUD_ENABLE)
> sctp_assoc_sync_pmtu(asoc);
> + } else if (!sctp_transport_pmtu_check(tp)) {
> + if (asoc->param_flags & SPP_PMTUD_ENABLE)
> + sctp_assoc_sync_pmtu(asoc);
> }
>
> if (asoc->pmtu_pending) {
> --
> 2.1.0
>
>
Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx>
