add a default limit for the amount of data xmlrpclib.gzip_decode will return (closes #16043)
diff --git a/Lib/xmlrpclib.py b/Lib/xmlrpclib.py
index 5354ec2..340dc51 100644
--- a/Lib/xmlrpclib.py
+++ b/Lib/xmlrpclib.py
@@ -49,6 +49,7 @@
# 2003-07-12 gp Correct marshalling of Faults
# 2003-10-31 mvl Add multicall support
# 2004-08-20 mvl Bump minimum supported Python version to 2.1
+# 2014-12-02 ch/doko Add workaround for gzip bomb vulnerability
#
# Copyright (c) 1999-2002 by Secret Labs AB.
# Copyright (c) 1999-2002 by Fredrik Lundh.
@@ -1165,10 +1166,13 @@
# in the HTTP header, as described in RFC 1952
#
# @param data The encoded data
+# @keyparam max_decode Maximum bytes to decode (20MB default), use negative
+# values for unlimited decoding
# @return the unencoded data
# @raises ValueError if data is not correctly coded.
+# @raises ValueError if max gzipped payload length exceeded
-def gzip_decode(data):
+def gzip_decode(data, max_decode=20971520):
"""gzip encoded data -> unencoded data
Decode data using the gzip content encoding as described in RFC 1952
@@ -1178,11 +1182,16 @@
f = StringIO.StringIO(data)
gzf = gzip.GzipFile(mode="rb", fileobj=f)
try:
- decoded = gzf.read()
+ if max_decode < 0: # no limit
+ decoded = gzf.read()
+ else:
+ decoded = gzf.read(max_decode + 1)
except IOError:
raise ValueError("invalid data")
f.close()
gzf.close()
+ if max_decode >= 0 and len(decoded) > max_decode:
+ raise ValueError("max gzipped payload length exceeded")
return decoded
##