From cae23393668bdabc3a0e438780ed1bc07e87c1dd Mon Sep 17 00:00:00 2001
From: ZHANG Dapeng <zdapeng@google.com>
Date: Tue, 24 Aug 2021 11:27:02 -0700
Subject: [PATCH] xds: fix RingHash LB null pointer issue (#8438)

---
 xds/src/main/java/io/grpc/xds/CdsLoadBalancer2.java | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/xds/src/main/java/io/grpc/xds/CdsLoadBalancer2.java b/xds/src/main/java/io/grpc/xds/CdsLoadBalancer2.java
index e91e76090a..036f77f7cd 100644
--- a/xds/src/main/java/io/grpc/xds/CdsLoadBalancer2.java
+++ b/xds/src/main/java/io/grpc/xds/CdsLoadBalancer2.java
@@ -188,8 +188,10 @@ final class CdsLoadBalancer2 extends LoadBalancer {
       if (root.result.lbPolicy() == LbPolicy.RING_HASH) {
         lbProvider = lbRegistry.getProvider("ring_hash");
         lbConfig = new RingHashConfig(root.result.minRingSize(), root.result.maxRingSize());
-      } else {
+      }
+      if (lbProvider == null) {
         lbProvider = lbRegistry.getProvider("round_robin");
+        lbConfig = null;
       }
       ClusterResolverConfig config = new ClusterResolverConfig(
           Collections.unmodifiableList(instances), new PolicySelection(lbProvider, lbConfig));