#767877 XMLSchemaParseError: Detected an entity reference loop

Package:
libxml2
Source:
libxml2
Description:
GNOME XML library
Submitter:
Juha Heinanen
Date:
2014-11-03 08:03:15 UTC
Severity:
important
#767877#5
Date:
2014-11-03 07:23:31 UTC
From:
To:
Dear Maintainer,

After security upgrade of the package from version
libxml2_2.8.0+dfsg1-7+wheezy1_amd64.deb to
libxml2_2.8.0+dfsg1-7+wheezy2_amd64.deb, sylkserver application (http://ag-
projects.com/debian/pool/main/s/sylkserver/sylkserver_2.7.2wheezy_all.deb with
http://ag-projects.com/debian/pool/main/p/python-sipsimple/python-
sipsimple_1.4.2wheezy_i386.deb ) does not anymore start.  The application
starts and works fine if I downgrade libxml2 back to
libxml2_2.8.0+dfsg1-7+wheezy1_amd64.deb.

At start, the application produces the following error messages:

Nov  2 19:50:32 rautu sylk-server[16896]: Using SIP SIMPLE SDK version 1.4.2
root@rautu:/home/jh/downloads# Nov  2 19:50:33 rautu sylk-server[16896]: using
set_wakeup_fd
Nov  2 19:50:33 rautu sylk-server[16896]: fatal error: failed to create
SylkServer: Detected an entity reference loop, line 30, column 38
Nov  2 19:50:33 rautu sylk-server[16896]: Traceback (most recent call last):
Nov  2 19:50:33 rautu sylk-server[16896]:   File "/usr/bin/sylk-server", line
70, in main
Nov  2 19:50:33 rautu sylk-server[16896]:     from sylk.server import
SylkServer
Nov  2 19:50:33 rautu sylk-server[16896]:   File "/usr/lib/python2.7/dist-
packages/sylk/server.py", line 13, in <module>
Nov  2 19:50:33 rautu sylk-server[16896]:     from sipsimple.account import
Account, BonjourAccount, AccountManager
Nov  2 19:50:33 rautu sylk-server[16896]:   File "/usr/lib/python2.7/dist-
packages/sipsimple/account/__init__.py", line 29, in <module>
Nov  2 19:50:33 rautu sylk-server[16896]:     from sipsimple.account.xcap
import XCAPManager
Nov  2 19:50:33 rautu sylk-server[16896]:   File "/usr/lib/python2.7/dist-
packages/sipsimple/account/xcap/__init__.py", line 39, in <module>
Nov  2 19:50:33 rautu sylk-server[16896]:     from sipsimple.payloads import
addressbook, commonpolicy, dialogrules, omapolicy, pidf, prescontent,
presrules, resourcelists, rlsservices, xcapcaps, xcapdiff
Nov  2 19:50:33 rautu sylk-server[16896]:   File "/usr/lib/python2.7/dist-
packages/sipsimple/payloads/xcapdiff.py", line 23, in <module>
Nov  2 19:50:33 rautu sylk-server[16896]:
XCAPDiffDocument.register_namespace(namespace, prefix=None,
schema='xcapdiff.xsd')
Nov  2 19:50:33 rautu sylk-server[16896]:   File "/usr/lib/python2.7/dist-
packages/sipsimple/payloads/__init__.py", line 201, in register_namespace
Nov  2 19:50:33 rautu sylk-server[16896]:     cls._update_schema()
Nov  2 19:50:33 rautu sylk-server[16896]:   File "/usr/lib/python2.7/dist-
packages/sipsimple/payloads/__init__.py", line 134, in _update_schema
Nov  2 19:50:33 rautu sylk-server[16896]:     cls.schema =
etree.XMLSchema(etree.XML(schema))
Nov  2 19:50:33 rautu sylk-server[16896]:   File "xmlschema.pxi", line 105, in
lxml.etree.XMLSchema.__init__ (src/lxml/lxml.etree.c:132605)
Nov  2 19:50:33 rautu sylk-server[16896]: XMLSchemaParseError: Detected an
entity reference loop, line 30, column 38

I would not expect a security upgrade of a library package to change its
behavior so that applications using the library suddenly stop working.