diff --git a/fail2ban/tests/clientreadertestcase.py b/fail2ban/tests/clientreadertestcase.py
index d721ef00..6fb125e3 100644
--- a/fail2ban/tests/clientreadertestcase.py
+++ b/fail2ban/tests/clientreadertestcase.py
@@ -53,10 +53,12 @@ class ConfigReaderTest(unittest.TestCase):
 			d_ = os.path.join(self.d, d)
 			if not os.path.exists(d_):
 				os.makedirs(d_)
-		open("%s/%s" % (self.d, fname), "w").write("""
+		f = open("%s/%s" % (self.d, fname), "w")
+		f.write("""
 [section]
 option = %s
 """ % value)
+		f.close()
 
 	def _remove(self, fname):
 		os.unlink("%s/%s" % (self.d, fname))
diff --git a/fail2ban/tests/filtertestcase.py b/fail2ban/tests/filtertestcase.py
index 053086d4..e540e41e 100644
--- a/fail2ban/tests/filtertestcase.py
+++ b/fail2ban/tests/filtertestcase.py
@@ -123,7 +123,7 @@ def _assert_correct_last_attempt(utest, filter_, output, count=None):
 
 	_assert_equal_entries(utest, found, output, count)
 
-def _copy_lines_between_files(fin, fout, n=None, skip=0, mode='a', terminal_line=""):
+def _copy_lines_between_files(in_, fout, n=None, skip=0, mode='a', terminal_line=""):
 	"""Copy lines from one file to another (which might be already open)
 
 	Returns open fout
@@ -132,8 +132,10 @@ def _copy_lines_between_files(fin, fout, n=None, skip=0, mode='a', terminal_line
 		# on old Python st_mtime is int, so we should give at least 1 sec so
 		# polling filter could detect the change
 		time.sleep(1)
-	if isinstance(fin, str): # pragma: no branch - only used with str in test cases
-		fin = open(fin, 'r')
+	if isinstance(in_, str): # pragma: no branch - only used with str in test cases
+		fin = open(in_, 'r')
+	else:
+		fin = in_
 	# Skip
 	for i in xrange(skip):
 		_ = fin.readline()
@@ -151,6 +153,9 @@ def _copy_lines_between_files(fin, fout, n=None, skip=0, mode='a', terminal_line
 		fout = open(fout, mode)
 	fout.write('\n'.join(lines))
 	fout.flush()
+	if isinstance(in_, str): # pragma: no branch - only used with str in test cases
+		# Opened earlier, therefore must close it
+		fin.close()
 	# to give other threads possibly some time to crunch
 	time.sleep(0.1)
 	return fout
@@ -291,7 +296,7 @@ class LogFileMonitor(unittest.TestCase):
 		#
 		# if we rewrite the file at once
 		self.file.close()
-		_copy_lines_between_files(GetFailures.FILENAME_01, self.name)
+		_copy_lines_between_files(GetFailures.FILENAME_01, self.name).close()
 		self.filter.getFailures(self.name)
 		_assert_correct_last_attempt(self, self.filter, GetFailures.FAILURES_01)
 
@@ -308,6 +313,7 @@ class LogFileMonitor(unittest.TestCase):
 	def testNewChangeViaGetFailures_move(self):
 		#
 		# if we move file into a new location while it has been open already
+		self.file.close()
 		self.file = _copy_lines_between_files(GetFailures.FILENAME_01, self.name,
 											  n=14, mode='w')
 		self.filter.getFailures(self.name)
@@ -316,7 +322,7 @@ class LogFileMonitor(unittest.TestCase):
 
 		# move aside, but leaving the handle still open...
 		os.rename(self.name, self.name + '.bak')
-		_copy_lines_between_files(GetFailures.FILENAME_01, self.name, skip=14)
+		_copy_lines_between_files(GetFailures.FILENAME_01, self.name, skip=14).close()
 		self.filter.getFailures(self.name)
 		_assert_correct_last_attempt(self, self.filter, GetFailures.FAILURES_01)
 		self.assertEqual(self.filter.failManager.getFailTotal(), 3)
@@ -454,7 +460,7 @@ def get_monitor_failures_testcase(Filter_):
 		def test_rewrite_file(self):
 			# if we rewrite the file at once
 			self.file.close()
-			_copy_lines_between_files(GetFailures.FILENAME_01, self.name)
+			_copy_lines_between_files(GetFailures.FILENAME_01, self.name).close()
 			self.assert_correct_last_attempt(GetFailures.FAILURES_01)
 
 			# What if file gets overridden
@@ -468,6 +474,7 @@ def get_monitor_failures_testcase(Filter_):
 
 		def test_move_file(self):
 			# if we move file into a new location while it has been open already
+			self.file.close()
 			self.file = _copy_lines_between_files(GetFailures.FILENAME_01, self.name,
 												  n=14, mode='w')
 			# Poll might need more time
@@ -477,25 +484,25 @@ def get_monitor_failures_testcase(Filter_):
 
 			# move aside, but leaving the handle still open...
 			os.rename(self.name, self.name + '.bak')
-			_copy_lines_between_files(GetFailures.FILENAME_01, self.name, skip=14)
+			_copy_lines_between_files(GetFailures.FILENAME_01, self.name, skip=14).close()
 			self.assert_correct_last_attempt(GetFailures.FAILURES_01)
 			self.assertEqual(self.filter.failManager.getFailTotal(), 3)
 
 			# now remove the moved file
 			_killfile(None, self.name + '.bak')
-			_copy_lines_between_files(GetFailures.FILENAME_01, self.name, n=100)
+			_copy_lines_between_files(GetFailures.FILENAME_01, self.name, n=100).close()
 			self.assert_correct_last_attempt(GetFailures.FAILURES_01)
 			self.assertEqual(self.filter.failManager.getFailTotal(), 6)
 
 
 		def test_new_bogus_file(self):
 			# to make sure that watching whole directory does not effect
-			_copy_lines_between_files(GetFailures.FILENAME_01, self.name, n=100)
+			_copy_lines_between_files(GetFailures.FILENAME_01, self.name, n=100).close()
 			self.assert_correct_last_attempt(GetFailures.FAILURES_01)
 
 			# create a bogus file in the same directory and see if that doesn't affect
-			open(self.name + '.bak2', 'w').write('')
-			_copy_lines_between_files(GetFailures.FILENAME_01, self.name, n=100)
+			open(self.name + '.bak2', 'w').close()
+			_copy_lines_between_files(GetFailures.FILENAME_01, self.name, n=100).close()
 			self.assert_correct_last_attempt(GetFailures.FAILURES_01)
 			self.assertEqual(self.filter.failManager.getFailTotal(), 6)
 			_killfile(None, self.name + '.bak2')