fix: [Bug Report] osrm-routed segfaults/asserts

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Unreleased
   - Changes from 6.0.0
     - Routing:
+      - FIXED: Prevent MLD route queries from updating removed heap nodes, avoiding `osrm-routed` segfaults/asserts [#7203](https://github.com/Project-OSRM/osrm-backend/issues/7203)
       - FIXED: Crash when route starts or ends at `type=manoeuvre` relation via node [#7287](https://github.com/Project-OSRM/osrm-backend/issues/7287)
     - Extraction:
       - ADDED: Emit warning when ways reference nodes not present in input data [#1596](https://github.com/Project-OSRM/osrm-backend/issues/1596)

include/engine/routing_algorithms/routing_base_mld.hpp

@@ -282,7 +282,7 @@ void insertOrUpdate(Heap &heap,
     {
         heap.Insert(node, weight, data);
     }
-    else if (weight < heapNode->weight)
+    else if (!heapNode->WasRemoved() && weight < heapNode->weight)
     {
         heapNode->data = data;
         heapNode->weight = weight;

include/util/query_heap.hpp

@@ -154,6 +154,8 @@ class QueryHeap
         NodeID node;
         Weight weight;
         Data data;
+
+        bool WasRemoved() const { return handle == HeapContainer::INVALID_HANDLE; }
     };
 
     template <typename... StorageArgs> explicit QueryHeap(StorageArgs... args) : node_index(args...)

unit_tests/engine/offline_facade.cpp

@@ -398,4 +398,28 @@ BOOST_AUTO_TEST_CASE(facade_uncompressed_methods)
     BOOST_CHECK_EQUAL(facade.GetUncompressedReverseDatasources(0).size(), 0);
 }
 
+BOOST_AUTO_TEST_CASE(insert_or_update_skips_removed_nodes)
+{
+    using QueryHeap = osrm::engine::SearchEngineData<
+        osrm::engine::routing_algorithms::offline::Algorithm>::QueryHeap;
+
+    QueryHeap heap(4, 0);
+    const osrm::engine::MultiLayerDijkstraHeapData initial_data{SPECIAL_NODEID, false};
+    const osrm::engine::MultiLayerDijkstraHeapData updated_data{1, true};
+
+    heap.Insert(1, {10}, initial_data);
+    BOOST_CHECK_EQUAL(heap.DeleteMin(), 1);
+    BOOST_CHECK(heap.WasRemoved(1));
+
+    osrm::engine::routing_algorithms::mld::insertOrUpdate(heap, 1, {5}, updated_data);
+
+    BOOST_CHECK(heap.WasRemoved(1));
+    BOOST_CHECK_EQUAL(from_alias<int>(heap.GetKey(1)), 10);
+
+    const auto heap_node = heap.GetHeapNodeIfWasInserted(1);
+    BOOST_REQUIRE(heap_node != nullptr);
+    BOOST_CHECK_EQUAL(heap_node->data.parent, SPECIAL_NODEID);
+    BOOST_CHECK_EQUAL(heap_node->data.from_clique_arc, false);
+}
+
 BOOST_AUTO_TEST_SUITE_END()