Examples of errors detected by the V6008 diagnostic

V6008. Potential null dereference.

Elasticsearch

V6008 Null dereference of 'line'. GoogleCloudStorageFixture.java(451)

private static PathTrie<RequestHandler> defaultHandlers(....) {
  ....
  handlers.insert("POST /batch/storage/v1", (request) -> {
    ....
      // Reads the body
      line = reader.readLine();
      byte[] batchedBody = new byte[0];
      if ((line != null) ||
          (line.startsWith("--" + boundary) == false))       // <=
      {
        batchedBody = line.getBytes(StandardCharsets.UTF_8);
      }
    ....
  });
  ....
}

Elasticsearch

V6008 Potential null dereference of 'followIndexMetadata'. TransportResumeFollowAction.java(171), TransportResumeFollowAction.java(170), TransportResumeFollowAction.java(194)

void start(
           ResumeFollowAction.Request request,
           String clusterNameAlias,
           IndexMetaData leaderIndexMetadata,
           IndexMetaData followIndexMetadata,
           ....) throws IOException
{
  MapperService mapperService = followIndexMetadata != null  // <=
                                ? ....
                                : null;
  validate(request,
           leaderIndexMetadata,
           followIndexMetadata,                              // <=
           leaderIndexHistoryUUIDs,
           mapperService);
  ....
}

Apache Hive

V6008 Potential null dereference of 'dagLock'. QueryTracker.java(557), QueryTracker.java(553)

private void handleFragmentCompleteExternalQuery(QueryInfo queryInfo)
{
  if (queryInfo.isExternalQuery())
  {
    ReadWriteLock dagLock = getDagLock(queryInfo.getQueryIdentifier());
    if (dagLock == null) {
      LOG.warn("Ignoring fragment completion for unknown query: {}",
          queryInfo.getQueryIdentifier());
    }
    boolean locked = dagLock.writeLock().tryLock();
    ....
  }
}

Apache Hive

V6008 Null dereference of 'buffer' in function 'unlockSingleBuffer'. MetadataCache.java(410), MetadataCache.java(465)

private boolean lockBuffer(LlapBufferOrBuffers buffers, ....)
{
  LlapAllocatorBuffer buffer = buffers.getSingleLlapBuffer();
  if (buffer != null) {                              // <=
    return lockOneBuffer(buffer, doNotifyPolicy);
  }
  LlapAllocatorBuffer[] bufferArray = buffers.getMultipleLlapBuffers();
  for (int i = 0; i < bufferArray.length; ++i) {
    if (lockOneBuffer(bufferArray[i], doNotifyPolicy)) continue;
    for (int j = 0; j < i; ++j) {
      unlockSingleBuffer(buffer, true);               // <=
    }
    ....
  }
  ....
}
....
private void unlockSingleBuffer(LlapAllocatorBuffer buffer, ....) {
  boolean isLastDecref = (buffer.decRef() == 0);      // <=
  if (isLastDecref) {
    ....
  }
}

Huawei Cloud

V6008 Potential null dereference of 'FileId.get(path)' in function '<init>'. TrackedFile.java(140), TrackedFile.java(115)

public TrackedFile(FileFlow<?> flow, Path path) throws IOException
{
  this(flow, path, FileId.get(path), ....);
}

Similar errors can be found in some other places:

• V6008 Potential null dereference of 'buffer'. PublishingQueue.java(518)

Huawei Cloud

V6008 Potential null dereference of 'dataTmpFile'. CacheManager.java(91)

@Override
public void putToCache(PutRecordsRequest putRecordsRequest)
{
  ....
  if (dataTmpFile == null || !dataTmpFile.exists())
  {
    try
    {
      dataTmpFile.createNewFile();  // <=
    }
    catch (IOException e)
    {
      LOGGER.error("Failed to create cache tmp file, return.", e);
      return ;
    }
  }
  ....
}

Ghidra

V6008 Null dereference of 'selectedNode' in function 'setViewPanel'. OptionsPanel.java(266)

private void processSelection(OptionsTreeNode selectedNode) {
  if (selectedNode == null) {
    setViewPanel(defaultPanel, selectedNode); // <=
    return;
  }
  ....
}
private void setViewPanel(JComponent component, OptionsTreeNode selectedNode) {
  ....
  setHelpLocation(component, selectedNode);
  ....
}
private void setHelpLocation(JComponent component, OptionsTreeNode node) {
  Options options = node.getOptions();
  ....
}

XMage

V6008 Null dereference of 'savedSpecialRares'. DragonsMaze.java(230)

public final class DragonsMaze extends ExpansionSet {
  ....
  private List<CardInfo> savedSpecialRares = new ArrayList<>();
  ....
  @Override
  public List<CardInfo> getSpecialRare() {
    if (savedSpecialRares == null) {                    // <=
      CardCriteria criteria = new CardCriteria();
      criteria.setCodes("GTC").name("Breeding Pool");
      savedSpecialRares.addAll(....);                   // <=
      criteria = new CardCriteria();
      criteria.setCodes("GTC").name("Godless Shrine");
      savedSpecialRares.addAll(....);
      ....
    }
    return new ArrayList<>(savedSpecialRares);
  }
}

Similar errors can be found in some other places:

• V6008 Null dereference of 'match'. TableController.java(973)

WildFly

V6008 Null dereference of 'tc'. ExternalPooledConnectionFactoryService.java(382)

private void createService(....) throws Exception {
  ....
  for (TransportConfiguration tc : connectors) {
    if (tc == null) {
      throw MessagingLogger.ROOT_LOGGER.connectorNotDefined(tc.getName());
    }
  }
  ....
}

Rhino

V6008 Potential null dereference of 'generatorState' in function 'freezeGenerator'. Interpreter.java(1244), Interpreter.java(3188)

public final class Interpreter extends Icode implements Evaluator {
  ....
  private static Object interpretLoop(Context cx,
                                      CallFrame frame,
                                      Object throwable) {

    GeneratorState generatorState = null;
    if (throwable != null) {
      if (throwable instanceof GeneratorState) {
        generatorState = (GeneratorState) throwable;
        ....
      } else if (!(throwable instanceof ContinuationJump)) {
        Kit.codeBug();
      }
    }
    ....
    StateLoop:
    for (; ; ) {
      ....
      if (throwable != null) {
        ....
      } else {
        if (generatorState == null && frame.frozen) Kit.codeBug();
      }

      for (; ; ) {
        ....
        int op = iCode[frame.pc++];
        jumplessRun:
        {
          switch (op) {
            ....
            case ....:
              {
                if (!frame.frozen) {
                  return freezeGenerator(....,
                                         generatorState, // <=
                                         ....);
                }
                ....
              }
            // many more cases
            ....
          }
        }
        ....
      }
      ....
    }
    ....
  }
  ....
  private static Object freezeGenerator(....,
                                        GeneratorState generatorState,
                                        ....) {
    if (generatorState.operation == NativeGenerator.GENERATOR_CLOSE){     // <=
        // Error: no yields when generator is closing
        throw ScriptRuntime.typeErrorById("msg.yield.closing");
    }
    ....
  }
}