1 files changed, 79 insertions, 14 deletions

diff --git a/net/tipc/link.c b/net/tipc/link.c
index e215b4ba6a4b..2c274777b2dd 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -180,6 +180,7 @@ struct tipc_link {
 
 	/* Fragmentation/reassembly */
 	struct sk_buff *reasm_buf;
+	struct sk_buff *reasm_tnlmsg;
 
 	/* Broadcast */
 	u16 ackers;
@@ -897,8 +898,10 @@ void tipc_link_reset(struct tipc_link *l)
 	l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
 	l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
 	kfree_skb(l->reasm_buf);
+	kfree_skb(l->reasm_tnlmsg);
 	kfree_skb(l->failover_reasm_skb);
 	l->reasm_buf = NULL;
+	l->reasm_tnlmsg = NULL;
 	l->failover_reasm_skb = NULL;
 	l->rcv_unacked = 0;
 	l->snd_nxt = 1;
@@ -940,6 +943,9 @@ int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
 	int rc = 0;
 
 	if (unlikely(msg_size(hdr) > mtu)) {
+		pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
+			skb_queue_len(list), msg_user(hdr),
+			msg_type(hdr), msg_size(hdr), mtu);
 		skb_queue_purge(list);
 		return -EMSGSIZE;
 	}
@@ -1233,6 +1239,7 @@ static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
 			     struct sk_buff_head *inputq)
 {
 	struct sk_buff **reasm_skb = &l->failover_reasm_skb;
+	struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
 	struct sk_buff_head *fdefq = &l->failover_deferdq;
 	struct tipc_msg *hdr = buf_msg(skb);
 	struct sk_buff *iskb;
@@ -1240,40 +1247,56 @@ static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
 	int rc = 0;
 	u16 seqno;
 
-	/* SYNCH_MSG */
-	if (msg_type(hdr) == SYNCH_MSG)
-		goto drop;
+	if (msg_type(hdr) == SYNCH_MSG) {
+		kfree_skb(skb);
+		return 0;
+	}
 
-	/* FAILOVER_MSG */
-	if (!tipc_msg_extract(skb, &iskb, &ipos)) {
-		pr_warn_ratelimited("Cannot extract FAILOVER_MSG, defq: %d\n",
-				    skb_queue_len(fdefq));
-		return rc;
+	/* Not a fragment? */
+	if (likely(!msg_nof_fragms(hdr))) {
+		if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
+			pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
+					    skb_queue_len(fdefq));
+			return 0;
+		}
+		kfree_skb(skb);
+	} else {
+		/* Set fragment type for buf_append */
+		if (msg_fragm_no(hdr) == 1)
+			msg_set_type(hdr, FIRST_FRAGMENT);
+		else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
+			msg_set_type(hdr, FRAGMENT);
+		else
+			msg_set_type(hdr, LAST_FRAGMENT);
+
+		if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
+			/* Successful but non-complete reassembly? */
+			if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
+				return 0;
+			pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
+			return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
+		}
+		iskb = skb;
 	}
 
 	do {
 		seqno = buf_seqno(iskb);
-
 		if (unlikely(less(seqno, l->drop_point))) {
 			kfree_skb(iskb);
 			continue;
 		}
-
 		if (unlikely(seqno != l->drop_point)) {
 			__tipc_skb_queue_sorted(fdefq, seqno, iskb);
 			continue;
 		}
 
 		l->drop_point++;
-
 		if (!tipc_data_input(l, iskb, inputq))
 			rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
 		if (unlikely(rc))
 			break;
 	} while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
 
-drop:
-	kfree_skb(skb);
 	return rc;
 }
 
@@ -1663,15 +1686,18 @@ void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
 	struct sk_buff *skb, *tnlskb;
 	struct tipc_msg *hdr, tnlhdr;
 	struct sk_buff_head *queue = &l->transmq;
-	struct sk_buff_head tmpxq, tnlq;
+	struct sk_buff_head tmpxq, tnlq, frags;
 	u16 pktlen, pktcnt, seqno = l->snd_nxt;
+	bool pktcnt_need_update = false;
 	u16 syncpt;
+	int rc;
 
 	if (!tnl)
 		return;
 
 	skb_queue_head_init(&tnlq);
 	skb_queue_head_init(&tmpxq);
+	skb_queue_head_init(&frags);
 
 	/* At least one packet required for safe algorithm => add dummy */
 	skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
@@ -1727,6 +1753,39 @@ tnl:
 		if (queue == &l->backlogq)
 			msg_set_seqno(hdr, seqno++);
 		pktlen = msg_size(hdr);
+
+		/* Tunnel link MTU is not large enough? This could be
+		 * due to:
+		 * 1) Link MTU has just changed or set differently;
+		 * 2) Or FAILOVER on the top of a SYNCH message
+		 *
+		 * The 2nd case should not happen if peer supports
+		 * TIPC_TUNNEL_ENHANCED
+		 */
+		if (pktlen > tnl->mtu - INT_H_SIZE) {
+			if (mtyp == FAILOVER_MSG &&
+			    (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
+				rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
+						       &frags);
+				if (rc) {
+					pr_warn("%sunable to frag msg: rc %d\n",
+						link_co_err, rc);
+					return;
+				}
+				pktcnt += skb_queue_len(&frags) - 1;
+				pktcnt_need_update = true;
+				skb_queue_splice_tail_init(&frags, &tnlq);
+				continue;
+			}
+			/* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
+			 * => Just warn it and return!
+			 */
+			pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
+					    link_co_err, msg_user(hdr),
+					    msg_type(hdr), msg_size(hdr));
+			return;
+		}
+
 		msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
 		tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
 		if (!tnlskb) {
@@ -1742,6 +1801,12 @@ tnl:
 		goto tnl;
 	}
 
+	if (pktcnt_need_update)
+		skb_queue_walk(&tnlq, skb) {
+			hdr = buf_msg(skb);
+			msg_set_msgcnt(hdr, pktcnt);
+		}
+
 	tipc_link_xmit(tnl, &tnlq, xmitq);
 
 	if (mtyp == FAILOVER_MSG) {