[Python-checkins] cpython (2.7): Issue #24467: Fixed possible buffer over-read in bytearray. The bytearray

Mon Jun 29 20:19:25 CEST 2015

https://hg.python.org/cpython/rev/a887ce8611d2
changeset: 96717:a887ce8611d2
branch: 2.7
user: Serhiy Storchaka <storchaka at gmail.com>
date: Mon Jun 29 21:13:54 2015 +0300
summary:
 Issue #24467: Fixed possible buffer over-read in bytearray. The bytearray
object now always allocates place for trailing null byte and it's buffer now
is always null-terminated.
files:
 Lib/test/test_bytes.py | 19 ++++++++++++++++++-
 Misc/NEWS | 4 ++++
 Objects/bytearrayobject.c | 4 +++-
 3 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py
--- a/Lib/test/test_bytes.py
+++ b/Lib/test/test_bytes.py
@@ -722,10 +722,27 @@
 for i in range(100):
 b += b"x"
 alloc = b.__alloc__()
- self.assertTrue(alloc >= len(b))
+ self.assertGreater(alloc, len(b)) # including trailing null byte
 if alloc not in seq:
 seq.append(alloc)
 
+ def test_init_alloc(self):
+ b = bytearray()
+ def g():
+ for i in range(1, 100):
+ yield i
+ a = list(b)
+ self.assertEqual(a, list(range(1, len(a)+1)))
+ self.assertEqual(len(b), len(a))
+ self.assertLessEqual(len(b), i)
+ alloc = b.__alloc__()
+ self.assertGreater(alloc, len(b)) # including trailing null byte
+ b.__init__(g())
+ self.assertEqual(list(b), list(range(1, 100)))
+ self.assertEqual(len(b), 99)
+ alloc = b.__alloc__()
+ self.assertGreater(alloc, len(b))
+
 def test_extend(self):
 orig = b'hello'
 a = bytearray(orig)
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,10 @@
 Core and Builtins
 -----------------
 
+- Issue #24467: Fixed possible buffer over-read in bytearray. The bytearray
+ object now always allocates place for trailing null byte and it's buffer now
+ is always null-terminated.
+
 - Issue #19543: encode() and decode() methods and constructors of str,
 unicode and bytearray classes now emit deprecation warning for known
 non-text encodings when Python is ran with the -3 option.
diff --git a/Objects/bytearrayobject.c b/Objects/bytearrayobject.c
--- a/Objects/bytearrayobject.c
+++ b/Objects/bytearrayobject.c
@@ -897,8 +897,10 @@
 goto error;
 
 /* Append the byte */
- if (Py_SIZE(self) < self->ob_alloc)
+ if (Py_SIZE(self) + 1 < self->ob_alloc) {
 Py_SIZE(self)++;
+ PyByteArray_AS_STRING(self)[Py_SIZE(self)] = '0円';
+ }
 else if (PyByteArray_Resize((PyObject *)self, Py_SIZE(self)+1) < 0)
 goto error;
 self->ob_bytes[Py_SIZE(self)-1] = value;
-- 
Repository URL: https://hg.python.org/cpython
