C++: Extend the taint model and accept test changes.

Author: MathiasVP

cpp/ql/lib/semmle/code/cpp/models/implementations/Strtol.qll

@@ -25,6 +25,9 @@ private class Strtol extends AliasFunction, ArrayFunction, TaintFunction, SideEf
       input.isParameterDeref(0)
     ) and
     output.isReturnValue()
+    or
+    input.isParameter(0) and
+    output.isParameterDeref(1)
   }
 
   override predicate parameterNeverEscapes(int i) {

cpp/ql/test/library-tests/dataflow/taint-tests/localTaint.expected

@@ -6636,6 +6636,7 @@ WARNING: Module TaintTracking has been deprecated and may be removed in future (
 | taint.cpp:728:17:728:23 | 0 | taint.cpp:732:8:732:13 | endptr |  |
 | taint.cpp:729:11:729:16 | call to strtol | taint.cpp:730:7:730:7 | l |  |
 | taint.cpp:729:18:729:23 | source | taint.cpp:729:11:729:16 | call to strtol | TAINT |
+| taint.cpp:729:18:729:23 | source | taint.cpp:729:26:729:32 | ref arg & ... | TAINT |
 | taint.cpp:729:26:729:32 | ref arg & ... | taint.cpp:729:27:729:32 | endptr [inner post update] |  |
 | taint.cpp:729:26:729:32 | ref arg & ... | taint.cpp:731:7:731:12 | endptr |  |
 | taint.cpp:729:26:729:32 | ref arg & ... | taint.cpp:732:8:732:13 | endptr |  |

cpp/ql/test/library-tests/dataflow/taint-tests/taint.cpp

@@ -728,6 +728,6 @@ void test_strtol(char *source) {
 	char* endptr = nullptr;
 	long l = strtol(source, &endptr, 10);
 	sink(l); // $ ast,ir
-	sink(endptr); // $ MISSING: ast,ir
-	sink(*endptr); // $ MISSING: ast,ir
+	sink(endptr); // $ ast,ir
+	sink(*endptr); // $ ast,ir
 }