TensorFlow vulnerable to null-dereference in `mlir::tfg::GraphDefImporter::ConvertNodeDef`

ImpactWhen mlir::tfg::GraphDefImporter::ConvertNodeDef tries to convert NodeDefs without an op name, it crashes.cppStatus GraphDefImporter::ConvertNodeDefOpBuilder , ConversionState , const NodeDef VLOG4 opdef; else auto it = functionopdefs.findnode.op; if it == functionopdefs.end return...