[SRU,Xenial,3/7] sctp: add dst_pending_confirm flag

Message ID 20170908070142.4440-4-daniel.axtens@canonical.com
State New
Headers show
Series
  • Fixes for LP#1715812
Related show

Commit Message

Daniel Axtens Sept. 8, 2017, 7:01 a.m.
From: Julian Anastasov <ja@ssi.bg>

BugLink: https://bugs.launchpad.net/bugs/1715812

Add new transport flag to allow sockets to confirm neighbour.
When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.
The flag is propagated from transport to every packet.
It is reset when cached dst is reset.

Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 5110effee8fd ("net: Do delayed neigh confirmation.")
Fixes: f2bb4bedf35d ("ipv4: Cache output routes in fib_info nexthops.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(backported from commit c86a773c78025f5b825bacd7b846f4fa60dc0317)
Signed-off-by: Daniel Axtens <daniel.axtens@canonical.com>
---
 include/net/sctp/sctp.h    |  6 ++----
 include/net/sctp/structs.h |  4 ++++
 net/sctp/associola.c       |  3 +--
 net/sctp/output.c          | 10 +++++++++-
 net/sctp/outqueue.c        |  2 +-
 net/sctp/sm_make_chunk.c   |  6 ++----
 net/sctp/sm_sideeffect.c   |  2 +-
 net/sctp/socket.c          |  4 ++--
 net/sctp/transport.c       | 16 +++++++++++++++-
 9 files changed, 37 insertions(+), 16 deletions(-)

Patch

diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index ce13cf20f625..9e61ca2bd40e 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -592,10 +592,8 @@  static inline void sctp_v4_map_v6(union sctp_addr *addr)
  */
 static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
 {
-	if (t->dst && !dst_check(t->dst, t->dst_cookie)) {
-		dst_release(t->dst);
-		t->dst = NULL;
-	}
+	if (t->dst && !dst_check(t->dst, t->dst_cookie))
+		sctp_transport_dst_release(t);
 
 	return t->dst;
 }
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index eea9bdeecba2..422785b7a255 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -830,6 +830,8 @@  struct sctp_transport {
 
 	__u32 burst_limited;	/* Holds old cwnd when max.burst is applied */
 
+	__u32 dst_pending_confirm;	/* need to confirm neighbour */
+
 	/* Destination */
 	struct dst_entry *dst;
 	/* Source address. */
@@ -966,6 +968,8 @@  unsigned long sctp_transport_timeout(struct sctp_transport *);
 void sctp_transport_reset(struct sctp_transport *);
 void sctp_transport_update_pmtu(struct sock *, struct sctp_transport *, u32);
 void sctp_transport_immediate_rtx(struct sctp_transport *);
+void sctp_transport_dst_release(struct sctp_transport *t);
+void sctp_transport_dst_confirm(struct sctp_transport *t);
 
 
 /* This is the structure we use to queue packets as they come into
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 559afd0ee7de..7a0e32607c75 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -810,8 +810,7 @@  void sctp_assoc_control_transport(struct sctp_association *asoc,
 		if (transport->state != SCTP_UNCONFIRMED)
 			transport->state = SCTP_INACTIVE;
 		else {
-			dst_release(transport->dst);
-			transport->dst = NULL;
+			sctp_transport_dst_release(transport);
 			ulp_notify = false;
 		}
 
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 9d610eddd19e..5d06aaa270ff 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -380,6 +380,7 @@  int sctp_packet_transmit(struct sctp_packet *packet)
 {
 	struct sctp_transport *tp = packet->transport;
 	struct sctp_association *asoc = tp->asoc;
+	int confirm;
 	struct sctphdr *sh;
 	struct sk_buff *nskb;
 	struct sctp_chunk *chunk, *tmp;
@@ -592,7 +593,14 @@  int sctp_packet_transmit(struct sctp_packet *packet)
 	pr_debug("***sctp_transmit_packet*** skb->len:%d\n", nskb->len);
 
 	nskb->ignore_df = packet->ipfragok;
-	tp->af_specific->sctp_xmit(nskb, tp);
+	confirm = tp->dst_pending_confirm;
+	if (confirm)
+		skb_set_dst_pending_confirm(nskb, 1);
+	/* neighbour should be confirmed on successful transmission or
+	 * positive error
+	 */
+	if (tp->af_specific->sctp_xmit(nskb, tp) >= 0 && confirm)
+		tp->dst_pending_confirm = 0;
 
 out:
 	sctp_packet_reset(packet);
diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index c0380cfb16ae..250159d28570 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -1563,7 +1563,7 @@  static void sctp_check_transmitted(struct sctp_outq *q,
 
 		if (forward_progress) {
 			if (transport->dst)
-				dst_confirm(transport->dst);
+				sctp_transport_dst_confirm(transport);
 		}
 	}
 
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 5d6a03fad378..1d79c1e48c5e 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -3308,8 +3308,7 @@  static void sctp_asconf_param_success(struct sctp_association *asoc,
 		local_bh_enable();
 		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
 				transports) {
-			dst_release(transport->dst);
-			transport->dst = NULL;
+			sctp_transport_dst_release(transport);
 		}
 		break;
 	case SCTP_PARAM_DEL_IP:
@@ -3323,8 +3322,7 @@  static void sctp_asconf_param_success(struct sctp_association *asoc,
 		local_bh_enable();
 		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
 				transports) {
-			dst_release(transport->dst);
-			transport->dst = NULL;
+			sctp_transport_dst_release(transport);
 		}
 		break;
 	default:
diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 6098d4c42fa9..388307b5e139 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -731,7 +731,7 @@  static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
 	 * forward progress.
 	 */
 	if (t->dst)
-		dst_confirm(t->dst);
+		sctp_transport_dst_confirm(t);
 
 	/* The receiver of the HEARTBEAT ACK should also perform an
 	 * RTT measurement for that destination transport address
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 3ebf3b652d60..88a67d2401a0 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -590,7 +590,7 @@  static int sctp_send_asconf_add_ip(struct sock		*sk,
 			list_for_each_entry(trans,
 			    &asoc->peer.transport_addr_list, transports) {
 				/* Clear the source and route cache */
-				dst_release(trans->dst);
+				sctp_transport_dst_release(trans);
 				trans->cwnd = min(4*asoc->pathmtu, max_t(__u32,
 				    2*asoc->pathmtu, 4380));
 				trans->ssthresh = asoc->peer.i.a_rwnd;
@@ -841,7 +841,7 @@  skip_mkasconf:
 		 */
 		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
 					transports) {
-			dst_release(transport->dst);
+			sctp_transport_dst_release(transport);
 			sctp_transport_route(transport, NULL,
 					     sctp_sk(asoc->base.sk));
 		}
diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index aab9e3f29755..238dd57911fe 100644
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -222,7 +222,7 @@  void sctp_transport_pmtu(struct sctp_transport *transport, struct sock *sk)
 {
 	/* If we don't have a fresh route, look one up */
 	if (!transport->dst || transport->dst->obsolete) {
-		dst_release(transport->dst);
+		sctp_transport_dst_release(transport);
 		transport->af_specific->get_dst(transport, &transport->saddr,
 						&transport->fl, sk);
 	}
@@ -654,3 +654,17 @@  void sctp_transport_immediate_rtx(struct sctp_transport *t)
 			sctp_transport_hold(t);
 	}
 }
+
+/* Drop dst */
+void sctp_transport_dst_release(struct sctp_transport *t)
+{
+	dst_release(t->dst);
+	t->dst = NULL;
+	t->dst_pending_confirm = 0;
+}
+
+/* Schedule neighbour confirm */
+void sctp_transport_dst_confirm(struct sctp_transport *t)
+{
+	t->dst_pending_confirm = 1;
+}