nl_l3::{add,del}_unicast_route: only update neighs for link scope routes

L3 Neighbours are always on-link, so we only need to update their state when handling link scope routes. Fixes enabling/disabling neighbours when handling default routes. Fixes: 0fdba0d ("nl_l3: only route l3 neighs if we have a route for them") Signed-off-by: Jonas Gorski <[email protected]>
bisdn · May 30, 2024 · fa06f41 · fa06f41
1 parent 0ef6a03
commit fa06f41
Showing 1 changed file with 36 additions and 32 deletions.
diff --git a/src/netlink/nl_l3.cc b/src/netlink/nl_l3.cc
@@ -1873,22 +1873,24 @@ int nl_l3::add_l3_unicast_route(rtnl_route *r, bool update_route) {
                << " rv=" << rv;
   }
 
-  VLOG(2) << __FUNCTION__ << ": enabling l3 neighs reachable by route " << r;
-  auto l3_neighs =
-      get_l3_neighs_of_prefix(unroutable_l3_neighs, rtnl_route_get_dst(r));
-  for (auto n : l3_neighs) {
-    auto neigh = nl->get_neighbour(n.ifindex, n.nh);
-    if (!neigh) {
-      // should we remove it from unroutable?
-      VLOG(2) << __FUNCTION__ << ": unknown l3 neigh ifindex=" << n.ifindex
-              << ", addr=" << n.nh;
-      continue;
-    }
+  if (rtnl_route_guess_scope(r) == RT_SCOPE_LINK) {
+    VLOG(2) << __FUNCTION__ << ": enabling l3 neighs reachable by route " << r;
+    auto l3_neighs =
+        get_l3_neighs_of_prefix(unroutable_l3_neighs, rtnl_route_get_dst(r));
+    for (auto n : l3_neighs) {
+      auto neigh = nl->get_neighbour(n.ifindex, n.nh);
+      if (!neigh) {
+        // should we remove it from unroutable?
+        VLOG(2) << __FUNCTION__ << ": unknown l3 neigh ifindex=" << n.ifindex
+                << ", addr=" << n.nh;
+        continue;
+      }
 
-    VLOG(2) << __FUNCTION__ << ": enabling l3 neigh " << neigh;
-    unroutable_l3_neighs.erase(n);
-    add_l3_neigh(neigh);
-    rtnl_neigh_put(neigh);
+      VLOG(2) << __FUNCTION__ << ": enabling l3 neigh " << neigh;
+      unroutable_l3_neighs.erase(n);
+      add_l3_neigh(neigh);
+      rtnl_neigh_put(neigh);
+    }
   }
 
   // cleanup
@@ -1966,24 +1968,26 @@ int nl_l3::del_l3_unicast_route(rtnl_route *r, bool keep_route) {
     }
   }
 
-  VLOG(2) << __FUNCTION__ << ": disabling l3 neighs reachable by route " << r;
-  auto l3_neighs =
-      get_l3_neighs_of_prefix(routable_l3_neighs, rtnl_route_get_dst(r));
-  for (auto n : l3_neighs) {
-    auto neigh = nl->get_neighbour(n.ifindex, n.nh);
-    if (!neigh) {
-      // neigh is already purged from nl cache, so neigh will be
-      // removed when handling the DEL_NEIGH notification
-      VLOG(2) << __FUNCTION__
-              << ": skipping non-existing l3 neigh ifindex=" << n.ifindex
-              << ", addr=" << n.nh;
-      continue;
-    }
+  if (rtnl_route_guess_scope(r) == RT_SCOPE_LINK) {
+    VLOG(2) << __FUNCTION__ << ": disabling l3 neighs reachable by route " << r;
+    auto l3_neighs =
+        get_l3_neighs_of_prefix(routable_l3_neighs, rtnl_route_get_dst(r));
+    for (auto n : l3_neighs) {
+      auto neigh = nl->get_neighbour(n.ifindex, n.nh);
+      if (!neigh) {
+        // neigh is already purged from nl cache, so neigh will be
+        // removed when handling the DEL_NEIGH notification
+        VLOG(2) << __FUNCTION__
+                << ": skipping non-existing l3 neigh ifindex=" << n.ifindex
+                << ", addr=" << n.nh;
+        continue;
+      }
 
-    VLOG(2) << __FUNCTION__ << ": disabling l3 neigh " << neigh;
-    del_l3_neigh(neigh);
-    rtnl_neigh_put(neigh);
-    unroutable_l3_neighs.emplace(n);
+      VLOG(2) << __FUNCTION__ << ": disabling l3 neigh " << neigh;
+      del_l3_neigh(neigh);
+      rtnl_neigh_put(neigh);
+      unroutable_l3_neighs.emplace(n);
+    }
   }
 
   std::deque<struct rtnl_neigh *> neighs;