Merge pull request #949 from ConsenSys/bugfix/lineno

Handle -1 case in solidity file mapping

mythril/analysis/report.py

@@ -107,6 +107,17 @@ class Issue:
 
         return issue
 
+    def _set_internal_compiler_error(self):
+        """
+        Adds the false positive to description and changes severity to low
+        """
+        self.severity = "Low"
+        self.description_tail += (
+            " This issue is reported for internal compiler generated code."
+        )
+        self.description = "%s\n%s" % (self.description_head, self.description_tail)
+        self.code = ""
+
     def add_code_info(self, contract):
         """
 
@@ -119,6 +130,8 @@ class Issue:
             self.filename = codeinfo.filename
             self.code = codeinfo.code
             self.lineno = codeinfo.lineno
+            if self.lineno is None:
+                self._set_internal_compiler_error()
             self.source_mapping = codeinfo.solc_mapping
         else:
             self.source_mapping = self.address

mythril/solidity/soliditycontract.py

@@ -161,11 +161,14 @@ class SolidityContract(EVMContract):
 
             if len(mapping) > 2 and len(mapping[2]) > 0:
                 idx = int(mapping[2])
-            lineno = (
-                self.solidity_files[idx]
-                .data.encode("utf-8")[0:offset]
-                .count("\n".encode("utf-8"))
-                + 1
-            )
+            if idx == -1:
+                lineno = None
+            else:
+                lineno = (
+                    self.solidity_files[idx]
+                    .data.encode("utf-8")[0:offset]
+                    .count("\n".encode("utf-8"))
+                    + 1
+                )
             prev_item = item
             mappings.append(SourceMapping(idx, offset, length, lineno, item))

mythril/support/truffle.py

@@ -194,7 +194,10 @@ def get_mappings(source, deployed_source_map):
         if len(mapping) > 2 and len(mapping[2]) > 0:
             idx = int(mapping[2])
 
-        lineno = source.encode("utf-8")[0:offset].count("\n".encode("utf-8")) + 1
+        if idx == -1:
+            lineno = None
+        else:
+            lineno = source.encode("utf-8")[0:offset].count("\n".encode("utf-8")) + 1
         prev_item = item
 
         mappings.append(SourceMapping(idx, offset, length, lineno, item))