[Python-checkins] bpo-31897: Convert unexpected errors when read bogus binary plists into InvalidFileException. (#4171)

Tue Oct 31 08:05:56 EDT 2017

https://github.com/python/cpython/commit/db91e0fe2417f075693a194a492b1699829871e7
commit: db91e0fe2417f075693a194a492b1699829871e7
branch: master
author: Serhiy Storchaka <storchaka at gmail.com>
committer: GitHub <noreply at github.com>
date: 2017年10月31日T14:05:53+02:00
summary:
bpo-31897: Convert unexpected errors when read bogus binary plists into InvalidFileException. (#4171)
files:
A Misc/NEWS.d/next/Library/2017-10-30-11-04-56.bpo-31897.yjwdEb.rst
M Lib/plistlib.py
M Lib/test/test_plistlib.py

diff --git a/Lib/plistlib.py b/Lib/plistlib.py
index 8262fb049e5..2113a2dc57b 100644
--- a/Lib/plistlib.py
+++ b/Lib/plistlib.py
@@ -557,7 +557,8 @@ def parse(self, fp):
 self._object_offsets = self._read_ints(num_objects, offset_size)
 return self._read_object(self._object_offsets[top_object])
 
- except (OSError, IndexError, struct.error):
+ except (OSError, IndexError, struct.error, OverflowError,
+ UnicodeDecodeError):
 raise InvalidFileException()
 
 def _get_size(self, tokenL):
@@ -575,6 +576,8 @@ def _read_ints(self, n, size):
 if size in _BINARY_FORMAT:
 return struct.unpack('>' + _BINARY_FORMAT[size] * n, data)
 else:
+ if not size or len(data) != size * n:
+ raise InvalidFileException()
 return tuple(int.from_bytes(data[i: i + size], 'big')
 for i in range(0, size * n, size))
 
diff --git a/Lib/test/test_plistlib.py b/Lib/test/test_plistlib.py
index 58b885f0228..7dd179a2c71 100644
--- a/Lib/test/test_plistlib.py
+++ b/Lib/test/test_plistlib.py
@@ -353,11 +353,13 @@ def test_controlcharacters(self):
 testString = "string containing %s" % c
 if i >= 32 or c in "\r\n\t":
 # \r, \n and \t are the only legal control chars in XML
- plistlib.dumps(testString, fmt=plistlib.FMT_XML)
+ data = plistlib.dumps(testString, fmt=plistlib.FMT_XML)
+ if c != "\r":
+ self.assertEqual(plistlib.loads(data), testString)
 else:
- self.assertRaises(ValueError,
- plistlib.dumps,
- testString)
+ with self.assertRaises(ValueError):
+ plistlib.dumps(testString, fmt=plistlib.FMT_XML)
+ plistlib.dumps(testString, fmt=plistlib.FMT_BINARY)
 
 def test_non_bmp_characters(self):
 pl = {'python': '\U0001f40d'}
@@ -366,6 +368,14 @@ def test_non_bmp_characters(self):
 data = plistlib.dumps(pl, fmt=fmt)
 self.assertEqual(plistlib.loads(data), pl)
 
+ def test_lone_surrogates(self):
+ for fmt in ALL_FORMATS:
+ with self.subTest(fmt=fmt):
+ with self.assertRaises(UnicodeEncodeError):
+ plistlib.dumps('\ud8ff', fmt=fmt)
+ with self.assertRaises(UnicodeEncodeError):
+ plistlib.dumps('\udcff', fmt=fmt)
+
 def test_nondictroot(self):
 for fmt in ALL_FORMATS:
 with self.subTest(fmt=fmt):
@@ -442,6 +452,56 @@ def test_large_timestamp(self):
 data = plistlib.dumps(d, fmt=plistlib.FMT_BINARY)
 self.assertEqual(plistlib.loads(data), d)
 
+ def test_invalid_binary(self):
+ for data in [
+ # too short data
+ b'',
+ # too large offset_table_offset and nonstandard offset_size
+ b'\x00\x08'
+ b'\x00\x00\x00\x00\x00\x00\x03\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x2a',
+ # integer overflow in offset_table_offset
+ b'\x00\x08'
+ b'\x00\x00\x00\x00\x00\x00\x01\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\xff\xff\xff\xff\xff\xff\xff\xff',
+ # offset_size = 0
+ b'\x00\x08'
+ b'\x00\x00\x00\x00\x00\x00\x00\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x09',
+ # ref_size = 0
+ b'\xa1\x01\x00\x08\x0a'
+ b'\x00\x00\x00\x00\x00\x00\x01\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x02'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x0b',
+ # integer overflow in offset
+ b'\x00\xff\xff\xff\xff\xff\xff\xff\xff'
+ b'\x00\x00\x00\x00\x00\x00\x08\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x09',
+ # invalid ASCII
+ b'\x51\xff\x08'
+ b'\x00\x00\x00\x00\x00\x00\x01\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x0a',
+ # invalid UTF-16
+ b'\x61\xd8\x00\x08'
+ b'\x00\x00\x00\x00\x00\x00\x01\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x01'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x0b',
+ ]:
+ with self.assertRaises(plistlib.InvalidFileException):
+ plistlib.loads(b'bplist00' + data, fmt=plistlib.FMT_BINARY)
+
 
 class TestPlistlibDeprecated(unittest.TestCase):
 def test_io_deprecated(self):
diff --git a/Misc/NEWS.d/next/Library/2017-10-30-11-04-56.bpo-31897.yjwdEb.rst b/Misc/NEWS.d/next/Library/2017-10-30-11-04-56.bpo-31897.yjwdEb.rst
new file mode 100644
index 00000000000..229472cb489
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2017-10-30-11-04-56.bpo-31897.yjwdEb.rst
@@ -0,0 +1,2 @@
+plistlib now catches more errors when read binary plists and raises
+InvalidFileException instead of unexpected exceptions.
