diff --git a/SIMTEST.txt b/SIMTEST.txt
index fecb209..d7db9b3 100644
--- a/SIMTEST.txt
+++ b/SIMTEST.txt
@@ -1,2 +1,3 @@
 Notes on simulation testing:
+    - Make sure your program works without fault injections
     - Trace the branch coverage of the test and find why some branches are never reached
diff --git a/src/chunk_server.c b/src/chunk_server.c
index 6eee73a..2af7873 100644
--- a/src/chunk_server.c
+++ b/src/chunk_server.c
@@ -553,6 +553,7 @@ process_metadata_server_auth_response(ChunkServer *state, int conn_idx, ByteView
     }
 
     directory_scanner_free(&scanner);
+    return 0;
 }
 
 static int
@@ -686,6 +687,10 @@ process_client_create_chunk(ChunkServer *state, int conn_idx, ByteView msg)
 
     sys_free(mem);
 
+    if (hash_set_insert(&state->cs_add_list, new_hash) < 0) {
+        assert(0); // TODO
+    }
+
     if (ret < 0)
         return send_error(&state->tcp, conn_idx, false, MESSAGE_TYPE_CREATE_CHUNK_ERROR, S("I/O error"));
 
@@ -737,6 +742,10 @@ process_client_upload_chunk(ChunkServer *state, int conn_idx, ByteView msg)
     if (ret < 0)
         return send_error(&state->tcp, conn_idx, false, MESSAGE_TYPE_UPLOAD_CHUNK_ERROR, S("I/O error"));
 
+    if (hash_set_insert(&state->cs_add_list, new_hash) < 0) {
+        assert(0); // TODO
+    }
+
     MessageWriter writer;
 
     ByteQueue *output = tcp_output_buffer(&state->tcp, conn_idx);
diff --git a/src/metadata_server.c b/src/metadata_server.c
index b2f5324..ce63de0 100644
--- a/src/metadata_server.c
+++ b/src/metadata_server.c
@@ -798,8 +798,6 @@ static int process_chunk_server_sync(MetadataServer *state,
         if (!file_tree_uses_hash(&state->file_tree, hash))
             continue;
 
-        // TODO: execution never reaches this point for some reason
-
         // If the chunk is properly replicated or under-replicated,
         // add it to the ms_add_list.