From: Carl Baldwin <carl@ecbaldwin.net>
Date: Wed, 29 Dec 2021 21:32:33 +0000 (-0700)
Subject: bgpd: ensure that the node gets unlocked in all cases
X-Git-Tag: pim6-testing-20220430~19^2
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=067ea16598a444b1ecfda5012f96acb038ba041e;p=matthieu%2Ffrr.git

bgpd: ensure that the node gets unlocked in all cases

The logic to unlock dest if iteration completed without iterating the
entire node was flawed. Specifically, if iteration terminated due to
`gr_deferred == 0` then the node would not get unlocked.

This change takes into account the fact that dest will be NULL only in
the case when the entire table was iterated and all nodes were already
unlocked. In any other case, it needs to be unlocked.

Signed-off-by: Carl Baldwin <carl@ecbaldwin.net>
---

diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index 7e2cb5c70c..df844a4992 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -3171,7 +3171,8 @@ int bgp_best_path_select_defer(struct bgp *bgp, afi_t afi, safi_t safi)
 
 	/* Process the route list */
 	for (dest = bgp_table_top(bgp->rib[afi][safi]);
-	     dest && bgp->gr_info[afi][safi].gr_deferred != 0;
+	     dest && bgp->gr_info[afi][safi].gr_deferred != 0 &&
+	     cnt < BGP_MAX_BEST_ROUTE_SELECT;
 	     dest = bgp_route_next(dest)) {
 		if (!CHECK_FLAG(dest->flags, BGP_NODE_SELECT_DEFER))
 			continue;
@@ -3180,10 +3181,13 @@ int bgp_best_path_select_defer(struct bgp *bgp, afi_t afi, safi_t safi)
 		bgp->gr_info[afi][safi].gr_deferred--;
 		bgp_process_main_one(bgp, dest, afi, safi);
 		cnt++;
-		if (cnt >= BGP_MAX_BEST_ROUTE_SELECT) {
-			bgp_dest_unlock_node(dest);
-			break;
-		}
+	}
+	/* If iteration stopped before the entire table was traversed then the
+	 * node needs to be unlocked.
+	 */
+	if (dest) {
+		bgp_dest_unlock_node(dest);
+		dest = NULL;
 	}
 
 	/* Send EOR message when all routes are processed */