zebra: Fix removal of routes on MetaQ when client goes down

It is possible that right before an upper level protocol dies
or is killed routes would be installed into zebra.  These routes
could be on the Meta-Q for early route-processing.  Leaving us with
a situation where the client is removed, and all it's routes that are
in the rib at that time, and then after that the MetaQ is run and the
routes are reprocessed leaving routes from an upper level daemon
post daemon going away from zebra's perspective.  These routes will
be abandoned.

Signed-off-by: Donald Sharp <sharpd@nvidia.com>

zebra/zebra_rib.c

@@ -3837,7 +3837,8 @@ static void rib_meta_queue_free(struct meta_queue *mq, struct list *l,
 }
 
 static void early_route_meta_queue_free(struct meta_queue *mq, struct list *l,
- struct zebra_vrf *zvrf)
+ const struct zebra_vrf *zvrf,
+ uint8_t proto, uint8_t instance)
 {
  struct zebra_early_route *ere;
  struct listnode *node, *nnode;
@@ -3846,6 +3847,10 @@ static void early_route_meta_queue_free(struct meta_queue *mq, struct list *l,
  if (zvrf && ere->re->vrf_id != zvrf->vrf->vrf_id)
  continue;
 
+ if (proto != ZEBRA_ROUTE_ALL &&
+ (proto != ere->re->type && instance != ere->re->instance))
+ continue;
+
  early_route_memory_free(ere);
  node->data = NULL;
  list_delete_node(l, node);
@@ -3884,7 +3889,8 @@ void meta_queue_free(struct meta_queue *mq, struct zebra_vrf *zvrf)
  evpn_meta_queue_free(mq, mq->subq[i], zvrf);
  break;
  case META_QUEUE_EARLY_ROUTE:
- early_route_meta_queue_free(mq, mq->subq[i], zvrf);
+ early_route_meta_queue_free(mq, mq->subq[i], zvrf,
+ ZEBRA_ROUTE_ALL, 0);
  break;
  case META_QUEUE_EARLY_LABEL:
  early_label_meta_queue_free(mq, mq->subq[i], zvrf);
@@ -4752,6 +4758,10 @@ unsigned long rib_score_proto(uint8_t proto, unsigned short instance)
  if (!zvrf)
  continue;
 
+ early_route_meta_queue_free(zrouter.mq,
+ zrouter.mq->subq[META_QUEUE_EARLY_ROUTE],
+ zvrf, proto, instance);
+
  cnt += rib_score_proto_table(proto, instance,
  zvrf->table[AFI_IP][SAFI_UNICAST])
  + rib_score_proto_table(