Blame SOURCES/00199-CVE-2013-1753.patch

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# HG changeset patch
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# User Benjamin Peterson <benjamin@python.org>
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# Date 1417828515 18000
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# Node ID d50096708b2d701937e78f525446d729fc28db88
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# Parent  923aac88a3cc76a95d5a04d9d3ece245147a8064
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add a default limit for the amount of data xmlrpclib.gzip_decode will return (closes #16043)
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diff --git a/Lib/test/test_xmlrpc.py b/Lib/test/test_xmlrpc.py
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--- a/Lib/test/test_xmlrpc.py
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+++ b/Lib/test/test_xmlrpc.py
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@@ -737,7 +737,7 @@ class GzipServerTestCase(BaseServerTestC
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         with cm:
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             p.pow(6, 8)
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-    def test_gsip_response(self):
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+    def test_gzip_response(self):
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         t = self.Transport()
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         p = xmlrpclib.ServerProxy(URL, transport=t)
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         old = self.requestHandler.encode_threshold
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@@ -750,6 +750,23 @@ class GzipServerTestCase(BaseServerTestC
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         self.requestHandler.encode_threshold = old
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         self.assertTrue(a>b)
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+    def test_gzip_decode_limit(self):
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+        max_gzip_decode = 20 * 1024 * 1024
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+        data = '\0' * max_gzip_decode
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+        encoded = xmlrpclib.gzip_encode(data)
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+        decoded = xmlrpclib.gzip_decode(encoded)
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+        self.assertEqual(len(decoded), max_gzip_decode)
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+
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+        data = '\0' * (max_gzip_decode + 1)
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+        encoded = xmlrpclib.gzip_encode(data)
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+
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+        with self.assertRaisesRegexp(ValueError,
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+                                     "max gzipped payload length exceeded"):
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+            xmlrpclib.gzip_decode(encoded)
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+
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+        xmlrpclib.gzip_decode(encoded, max_decode=-1)
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+
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+
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 #Test special attributes of the ServerProxy object
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 class ServerProxyTestCase(unittest.TestCase):
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     def setUp(self):
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diff --git a/Lib/xmlrpclib.py b/Lib/xmlrpclib.py
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--- a/Lib/xmlrpclib.py
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+++ b/Lib/xmlrpclib.py
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@@ -49,6 +49,7 @@
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 # 2003-07-12 gp  Correct marshalling of Faults
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 # 2003-10-31 mvl Add multicall support
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 # 2004-08-20 mvl Bump minimum supported Python version to 2.1
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+# 2014-12-02 ch/doko  Add workaround for gzip bomb vulnerability
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 #
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 # Copyright (c) 1999-2002 by Secret Labs AB.
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 # Copyright (c) 1999-2002 by Fredrik Lundh.
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@@ -1165,10 +1166,13 @@ def gzip_encode(data):
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 # in the HTTP header, as described in RFC 1952
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 #
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 # @param data The encoded data
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+# @keyparam max_decode Maximum bytes to decode (20MB default), use negative
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+#    values for unlimited decoding
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 # @return the unencoded data
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 # @raises ValueError if data is not correctly coded.
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+# @raises ValueError if max gzipped payload length exceeded
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-def gzip_decode(data):
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+def gzip_decode(data, max_decode=20971520):
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     """gzip encoded data -> unencoded data
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     Decode data using the gzip content encoding as described in RFC 1952
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@@ -1178,11 +1182,16 @@ def gzip_decode(data):
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     f = StringIO.StringIO(data)
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     gzf = gzip.GzipFile(mode="rb", fileobj=f)
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     try:
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-        decoded = gzf.read()
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+        if max_decode < 0: # no limit
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+            decoded = gzf.read()
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+        else:
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+            decoded = gzf.read(max_decode + 1)
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     except IOError:
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         raise ValueError("invalid data")
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     f.close()
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     gzf.close()
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+    if max_decode >= 0 and len(decoded) > max_decode:
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+        raise ValueError("max gzipped payload length exceeded")
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     return decoded
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 ##