gossipd: put common size restrictions on all maps.

We already limited pending_ann_map and early_ann_map to 10,000 entries:
do the same for pending_nannounces, pending_cupdates and early_cupdates.

Add CI_UNEXPECTED so CI gets upset if this happens unexpectedly.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Author: rustyrussell

gossipd/gossmap_manage.c

@@ -29,6 +29,7 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
+#define PENDING_LIMIT 10000
 #define GOSSIP_STORE_COMPACT_FILENAME "gossip_store.compact"
 
 struct pending_cannounce {
@@ -133,9 +134,24 @@ static void enqueue_cupdate(struct pending_cupdate ***queue,
 			    u32 fee_proportional_millionths,
 			    u32 timestamp,
 			    const u8 *update TAKES,
-			    const struct node_id *source_peer TAKES)
+			    const struct node_id *source_peer)
 {
-	struct pending_cupdate *pcu = tal(*queue, struct pending_cupdate);
+	struct pending_cupdate *pcu;
+
+	if (tal_count(*queue) > PENDING_LIMIT) {
+		static bool warned = false;
+		status_unusual_once(&warned,
+				    CI_UNEXPECTED
+				    "channel_updates being flooded by %s: dropping some",
+				    source_peer
+				    ? fmt_node_id(tmpctx, source_peer)
+				    : "unknown");
+		tal_free_if_taken(update);
+		tal_free_if_taken(source_peer);
+		return;
+	}
+
+	pcu = tal(*queue, struct pending_cupdate);
 
 	pcu->scid = scid;
 	pcu->signature = *signature;
@@ -159,7 +175,22 @@ static void enqueue_nannounce(struct pending_nannounce ***queue,
 			      const u8 *nannounce TAKES,
 			      const struct node_id *source_peer TAKES)
 {
-	struct pending_nannounce *pna = tal(*queue, struct pending_nannounce);
+	struct pending_nannounce *pna;
+
+	if (tal_count(*queue) > PENDING_LIMIT) {
+		static bool warned = false;
+		status_unusual_once(&warned,
+				    CI_UNEXPECTED
+				    "node_announcements being flooded by %s: dropping some",
+				    source_peer
+				    ? fmt_node_id(tmpctx, source_peer)
+				    : "unknown");
+		tal_free_if_taken(nannounce);
+		tal_free_if_taken(source_peer);
+		return;
+	}
+
+	pna = tal(*queue, struct pending_nannounce);
 
 	pna->node_id = *node_id;
 	pna->timestamp = timestamp;
@@ -183,8 +214,9 @@ static bool map_add(struct cannounce_map *map,
 		    struct pending_cannounce *pca)
 {
 	/* More than 10000 pending things?  Stop! */
-	if (map->count > 10000) {
+	if (map->count > PENDING_LIMIT) {
 		status_unusual_once(&map->flood_reported,
+				    CI_UNEXPECTED
 				    "%s being flooded by %s: dropping some",
 				    map->name,
 				    pca->source_peer