Merge branch 'dev-fix-data-dependency' into dev

examples/scripts/data_dependency.sol

@@ -102,3 +102,16 @@ contract PropagateThroughArguments {
         var_not_tainted = y;
     }
 }
+
+contract PropagateThroughReturnValue {
+  uint var_dependant;
+  uint var_state;
+
+  function foo() public {
+    var_dependant = bar();
+  }
+
+  function bar() internal returns (uint) {
+    return (var_state);
+  }
+}

slither/analyses/data_dependency/data_dependency.py

@@ -4,7 +4,7 @@
 from slither.core.declarations import (Contract, Enum, Function,
                                        SolidityFunction, SolidityVariable,
                                        SolidityVariableComposed, Structure)
-from slither.slithir.operations import Index, OperationWithLValue
+from slither.slithir.operations import Index, OperationWithLValue, InternalCall
 from slither.slithir.variables import (Constant, LocalIRVariable,
                                        ReferenceVariable, ReferenceVariableSSA,
                                        StateIRVariable, TemporaryVariable,
@@ -232,6 +232,8 @@ def add_dependency(lvalue, function, ir, is_protected):
             function.context[KEY_SSA_UNPROTECTED][lvalue] = set()
     if isinstance(ir, Index):
         read = [ir.variable_left]
+    elif isinstance(ir, InternalCall):
+        read = ir.function.return_values_ssa
     else:
         read = ir.read
     [function.context[KEY_SSA][lvalue].add(v) for v in read if not isinstance(v, Constant)]

slither/core/declarations/function.py

@@ -9,10 +9,8 @@ from slither.core.children.child_contract import ChildContract
 from slither.core.declarations.solidity_variables import (SolidityFunction,
                                                           SolidityVariable,
                                                           SolidityVariableComposed)
-from slither.core.expressions.identifier import Identifier
-from slither.core.expressions.index_access import IndexAccess
-from slither.core.expressions.member_access import MemberAccess
-from slither.core.expressions.unary_operation import UnaryOperation
+from slither.core.expressions import (Identifier, IndexAccess, MemberAccess,
+                                      UnaryOperation)
 from slither.core.source_mapping.source_mapping import SourceMapping
 from slither.core.variables.state_variable import StateVariable
 
@@ -43,6 +41,8 @@ class Function(ChildContract, SourceMapping):
         self._parameters_ssa = []
         self._returns = []
         self._returns_ssa = []
+        self._return_values = None
+        self._return_values_ssa = None
         self._vars_read = []
         self._vars_written = []
         self._state_vars_read = []
@@ -468,6 +468,36 @@ class Function(ChildContract, SourceMapping):
             self._expressions = expressions
         return self._expressions
 
+    @property
+    def return_values(self):
+        """
+            list(Return Values): List of the return values
+        """
+        from slither.core.cfg.node import NodeType
+        from slither.slithir.operations import Return
+
+        if self._return_values is None:
+            return_values = list()
+            returns = [n for n in self.nodes if n.type == NodeType.RETURN]
+            [return_values.extend(ir.values) for node in returns for ir in node.irs if isinstance(ir, Return)]
+            self._return_values = list(set(return_values))
+        return self._return_values
+
+    @property
+    def return_values_ssa(self):
+        """
+            list(Return Values in SSA form): List of the return values in ssa form
+        """
+        from slither.core.cfg.node import NodeType
+        from slither.slithir.operations import Return
+
+        if self._return_values_ssa is None:
+            return_values_ssa = list()
+            returns = [n for n in self.nodes if n.type == NodeType.RETURN]
+            [return_values_ssa.extend(ir.values) for node in returns for ir in node.irs_ssa if isinstance(ir, Return)]
+            self._return_values_ssa = list(set(return_values_ssa))
+        return self._return_values_ssa
+
     # endregion
     ###################################################################################
     ###################################################################################

slither/core/expressions/__init__.py

@@ -6,6 +6,7 @@ from .elementary_type_name_expression import ElementaryTypeNameExpression
 from .identifier import Identifier
 from .index_access import IndexAccess
 from .literal import Literal
+from .member_access import MemberAccess
 from .new_array import NewArray
 from .new_contract import NewContract
 from .new_elementary_type import NewElementaryType