Commit 6ff0f871 authored Apr 26, 2018 by Marcelo Ricardo Leitner Committed by David S. Miller Apr 27, 2018

sctp: introduce sctp_dst_mtu



Which makes sure that the MTU respects the minimum value of
SCTP_DEFAULT_MINSEGMENT and that it is correctly aligned.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 2521680e

include/net/sctp/sctp.h

+7 −2

Original line number	Diff line number	Diff line
		@@ -600,10 +600,15 @@ static inline __u32 sctp_mtu_payload(const struct sctp_sock *sp,
		return mtu ? mtu - overhead : overhead;
		}

		static inline __u32 sctp_dst_mtu(const struct dst_entry *dst)
		{
		return SCTP_TRUNC4(max_t(__u32, dst_mtu(dst),
		SCTP_DEFAULT_MINSEGMENT));
		}

		static inline bool sctp_transport_pmtu_check(struct sctp_transport *t)
		{
		__u32 pmtu = max_t(size_t, SCTP_TRUNC4(dst_mtu(t->dst)),
		SCTP_DEFAULT_MINSEGMENT);
		__u32 pmtu = sctp_dst_mtu(t->dst);

		if (t->pathmtu == pmtu)
		return true;

net/sctp/associola.c

+2 −4

Original line number	Diff line number	Diff line
		@@ -1405,11 +1405,9 @@ void sctp_assoc_sync_pmtu(struct sctp_association *asoc)
		return;

		/* Get the lowest pmtu of all the transports. */
		list_for_each_entry(t, &asoc->peer.transport_addr_list,
		transports) {
		list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
		if (t->pmtu_pending && t->dst) {
		sctp_transport_update_pmtu(
		t, SCTP_TRUNC4(dst_mtu(t->dst)));
		sctp_transport_update_pmtu(t, sctp_dst_mtu(t->dst));
		t->pmtu_pending = 0;
		}
		if (!pmtu \|\| (t->pathmtu < pmtu))

net/sctp/transport.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -242,9 +242,9 @@ void sctp_transport_pmtu(struct sctp_transport transport, struct sock sk)
		&transport->fl, sk);
		}

		if (transport->dst) {
		transport->pathmtu = SCTP_TRUNC4(dst_mtu(transport->dst));
		} else
		if (transport->dst)
		transport->pathmtu = sctp_dst_mtu(transport->dst);
		else
		transport->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
		}