bgpd: fix the add-path code to understand the mpls-vpn safi

In order to iterate over MPLS VPN routes, it's necessary to use
two nested loops (the outer loop iterates over the MPLS VPN RDs,
and the inner loop iterates over the VPN routes from that RD).

The add-path code wasn't doing this, which was leading to lots of
crashes when add-path was enabled for the MPLS VPN SAFI. This patch
fixes the problem.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

1 files changed, 61 insertions, 22 deletions

diff --git a/bgpd/bgp_addpath.c b/bgpd/bgp_addpath.c
index 55a86f99fc..c7fd1ba0e2 100644
--- a/bgpd/bgp_addpath.c
+++ b/bgpd/bgp_addpath.c
@@ -175,6 +175,28 @@ int bgp_addpath_tx_path(enum bgp_addpath_strat strat,
 	}
 }
 
+static void bgp_addpath_flush_type_rn(struct bgp *bgp, afi_t afi, safi_t safi,
+				      enum bgp_addpath_strat addpath_type,
+				      struct bgp_node *rn)
+{
+	struct bgp_path_info *pi;
+
+	idalloc_drain_pool(
+		bgp->tx_addpath.id_allocators[afi][safi][addpath_type],
+		&(rn->tx_addpath.free_ids[addpath_type]));
+	for (pi = bgp_node_get_bgp_path_info(rn); pi; pi = pi->next) {
+		if (pi->tx_addpath.addpath_tx_id[addpath_type]
+		    != IDALLOC_INVALID) {
+			idalloc_free(
+				bgp->tx_addpath
+					.id_allocators[afi][safi][addpath_type],
+				pi->tx_addpath.addpath_tx_id[addpath_type]);
+			pi->tx_addpath.addpath_tx_id[addpath_type] =
+				IDALLOC_INVALID;
+		}
+	}
+}
+
 /*
  * Purge all addpath ID's on a BGP instance associated with the addpath
  * strategy, and afi/safi combination. This lets us let go of all memory held to
@@ -185,26 +207,24 @@ int bgp_addpath_tx_path(enum bgp_addpath_strat strat,
 static void bgp_addpath_flush_type(struct bgp *bgp, afi_t afi, safi_t safi,
 				   enum bgp_addpath_strat addpath_type)
 {
-	struct bgp_node *rn;
-	struct bgp_path_info *pi;
+	struct bgp_node *rn, *nrn;
 
 	for (rn = bgp_table_top(bgp->rib[afi][safi]); rn;
 	     rn = bgp_route_next(rn)) {
-		idalloc_drain_pool(
-			bgp->tx_addpath.id_allocators[afi][safi][addpath_type],
-			&(rn->tx_addpath.free_ids[addpath_type]));
-		for (pi = bgp_node_get_bgp_path_info(rn); pi; pi = pi->next) {
-			if (pi->tx_addpath.addpath_tx_id[addpath_type]
-			    != IDALLOC_INVALID) {
-				idalloc_free(
-					bgp->tx_addpath
-						.id_allocators[afi][safi]
-							      [addpath_type],
-					pi->tx_addpath
-						.addpath_tx_id[addpath_type]);
-				pi->tx_addpath.addpath_tx_id[addpath_type] =
-					IDALLOC_INVALID;
-			}
+		if (safi == SAFI_MPLS_VPN) {
+			struct bgp_table *table;
+
+			table = bgp_node_get_bgp_table_info(rn);
+			if (!table)
+				continue;
+
+			for (nrn = bgp_table_top(table); nrn;
+			     nrn = bgp_route_next(nrn))
+				bgp_addpath_flush_type_rn(bgp, afi, safi,
+							  addpath_type, nrn);
+		} else {
+			bgp_addpath_flush_type_rn(bgp, afi, safi, addpath_type,
+						  rn);
 		}
 	}
 
@@ -234,8 +254,7 @@ static void bgp_addpath_populate_path(struct id_alloc *allocator,
 static void bgp_addpath_populate_type(struct bgp *bgp, afi_t afi, safi_t safi,
 				    enum bgp_addpath_strat addpath_type)
 {
-	struct bgp_node *rn;
-	struct bgp_path_info *bi;
+	struct bgp_node *rn, *nrn;
 	char buf[200];
 	struct id_alloc *allocator;
 
@@ -255,9 +274,29 @@ static void bgp_addpath_populate_type(struct bgp *bgp, afi_t afi, safi_t safi,
 	allocator = bgp->tx_addpath.id_allocators[afi][safi][addpath_type];
 
 	for (rn = bgp_table_top(bgp->rib[afi][safi]); rn;
-	     rn = bgp_route_next(rn))
-		for (bi = bgp_node_get_bgp_path_info(rn); bi; bi = bi->next)
-			bgp_addpath_populate_path(allocator, bi, addpath_type);
+	     rn = bgp_route_next(rn)) {
+		struct bgp_path_info *bi;
+
+		if (safi == SAFI_MPLS_VPN) {
+			struct bgp_table *table;
+
+			table = bgp_node_get_bgp_table_info(rn);
+			if (!table)
+				continue;
+
+			for (nrn = bgp_table_top(table); nrn;
+			     nrn = bgp_route_next(nrn))
+				for (bi = bgp_node_get_bgp_path_info(nrn); bi;
+				     bi = bi->next)
+					bgp_addpath_populate_path(allocator, bi,
+								  addpath_type);
+		} else {
+			for (bi = bgp_node_get_bgp_path_info(rn); bi;
+			     bi = bi->next)
+				bgp_addpath_populate_path(allocator, bi,
+							  addpath_type);
+		}
+	}
 }
 
 /*