[3.9] gh-115398: Expose Expat >=2.6.0 reparse deferral API (CVE-2023-52425) (GH-115623) #116272
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Allow controlling Expat >=2.6.0 reparse deferral (CVE-2023-52425) by adding five new methods:
xml.etree.ElementTree.XMLParser.flushxml.etree.ElementTree.XMLPullParser.flushxml.parsers.expat.xmlparser.GetReparseDeferralEnabledxml.parsers.expat.xmlparser.SetReparseDeferralEnabledxml.sax.expatreader.ExpatParser.flushBased on the "flush" idea from #115138 (comment) .
Includes code suggested-by: Snild Dolkow [email protected]
and by core dev Serhiy Storchaka.
(cherry picked from commit 6a95676)
XML_SetReparseDeferralEnabled#115398