From 5e0d1b1a32d8df616d58db73cfc551334a6bf711 Mon Sep 17 00:00:00 2001
From: Jonathan Hui <jonhui@google.com>
Date: Fri, 12 Nov 2021 12:22:38 -0800
Subject: [PATCH] [mle] record child netdata versions in
 `HandleChildUpdateRequest()` (#7157)

Thread Specification allows a parent to update child network data by
sending a unicast MLE Data Response. Receiving the child's Leader Data
in a MLE Child Update Request message should serve as an
acknowledgment when the network data is received.
---
 src/core/thread/mle_router.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/core/thread/mle_router.cpp b/src/core/thread/mle_router.cpp
index cfe200415..9fa9709bd 100644
--- a/src/core/thread/mle_router.cpp
+++ b/src/core/thread/mle_router.cpp
@@ -2481,6 +2481,15 @@ void MleRouter::HandleChildUpdateRequest(const Message &aMessage, const Ip6::Mes
     switch (ReadLeaderData(aMessage, leaderData))
     {
     case kErrorNone:
+        if (child->IsFullNetworkData())
+        {
+            child->SetNetworkDataVersion(leaderData.GetDataVersion());
+        }
+        else
+        {
+            child->SetNetworkDataVersion(leaderData.GetStableDataVersion());
+        }
+        break;
     case kErrorNotFound:
         break;
     default: