Issue #29: Fail more gracefully when no string table is found for dynamic.

diff --git a/elftools/elf/dynamic.py b/elftools/elf/dynamic.py
index e36598e7636c75f767e069eb92956b1b0031b267..6f88bf9e3f24ad56df60d8b26942c9b20ce12432 100644 (file)
--- a/elftools/elf/dynamic.py
+++ b/elftools/elf/dynamic.py
@@ -10,6 +10,7 @@ import itertools
 
 from .sections import Section
 from .segments import Segment
+from ..common.exceptions import ELFError
 from ..common.utils import struct_parse
 
 from .enums import ENUM_D_TAG
@@ -29,6 +30,8 @@ class DynamicTag(object):
          'DT_SUNW_FILTER'])
 
     def __init__(self, entry, stringtable):
+        if stringtable is None:
+            raise ELFError('Creating DynamicTag without string table')
         self.entry = entry
         if entry.d_tag in self._HANDLED_TAGS:
             setattr(self, entry.d_tag[3:].lower(),
@@ -114,6 +117,7 @@ class DynamicSegment(Segment, Dynamic):
         # So we must look for the dynamic section contained in the dynamic
         # segment, we do so by searching for the dynamic section whose content
         # is located at the same offset as the dynamic segment
+        stringtable = None
         for section in elffile.iter_sections():
             if (isinstance(section, DynamicSection) and
                     section['sh_offset'] == header['p_offset']):

diff --git a/test/test_dynamic.py b/test/test_dynamic.py
new file mode 100644 (file)
index 0000000..0ee9b35
--- /dev/null
+++ b/test/test_dynamic.py
@@ -0,0 +1,25 @@
+#-------------------------------------------------------------------------------
+# elftools tests
+#
+# Eli Bendersky (eliben@gmail.com)
+# This code is in the public domain
+#-------------------------------------------------------------------------------
+try:
+    import unittest2 as unittest
+except ImportError:
+    import unittest
+import os
+
+from utils import setup_syspath; setup_syspath()
+from elftools.common.exceptions import ELFError
+from elftools.elf.dynamic import DynamicTag
+
+
+class TestDynamicTag(unittest.TestCase):
+    def test_requires_stringtable(self):
+        with self.assertRaises(ELFError):
+            dt = DynamicTag('', None)
+
+
+if __name__ == '__main__':
+    unittest.main()