C++: Work around problems I can't seem to solve for access paths at sources and sinks.

Author: MathiasVP

cpp/ql/lib/semmle/code/cpp/dataflow/ExternalFlow.qll

@@ -953,6 +953,10 @@ private module Cached {
    */
   cached
   predicate sourceNode(DataFlow::Node node, string kind, string model) {
+    exists(SourceSinkInterpretationInput::InterpretNode n |
+      isSourceNode(n, kind, model) and n.asNode() = node
+    )
+    or
     node.(Nodes::FlowSummaryNode).isSource(kind, model)
   }
 

cpp/ql/lib/semmle/code/cpp/dataflow/internal/FlowSummaryImpl.qll

@@ -376,7 +376,10 @@ private class SourceModelCall extends Public::SourceElement instanceof Call {
   private string ext;
 
   SourceModelCall() {
-    sourceModel(namespace, type, subtypes, name, signature, ext, _, _, _, _) and
+    exists(string output |
+      sourceModel(namespace, type, subtypes, name, signature, ext, output, _, _, _) and
+      output.matches("%" + Input::encodeContent(_, _) + "%")
+    ) and
     this.getTarget() = interpretElement(namespace, type, subtypes, name, signature, ext)
   }