From 9f7a664fe35c40cc9b1a4ebec4fc990dc45370f3 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 25 Oct 2019 15:22:40 -0400 Subject: Avoid failure when selecting a namespace node in XMLTABLE. It appears that libxml2 doesn't bother to set the "children" field of an XML_NAMESPACE_DECL node to null; that field just contains garbage. In v10 and v11, this can result in a crash in XMLTABLE(). The rewrite done in commit 251cf2e27 fixed this, somewhat accidentally, in v12. We're not going to back-patch 251cf2e27, however. The case apparently doesn't have wide use, so rather than risk introducing other problems, just add a safety check to throw an error. Even though no bug manifests in v12/HEAD, add the relevant test case there too, to prevent future regressions. Chapman Flack (per private report) --- src/backend/utils/adt/xml.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'src/backend/utils/adt/xml.c') diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c index 48d98e96cf5..edac2754aba 100644 --- a/src/backend/utils/adt/xml.c +++ b/src/backend/utils/adt/xml.c @@ -4612,6 +4612,12 @@ XmlTableGetValue(TableFuncScanState *state, int colnum, xmlChar *str; xmlNodePtr node; + node = xpathobj->nodesetval->nodeTab[0]; + if (node->type == XML_NAMESPACE_DECL) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("XMLTABLE cannot cast a namespace node to a non-XML result type"))); + /* * Most nodes (elements and even attributes) store their data * in children nodes. If they don't have children nodes, it @@ -4619,7 +4625,6 @@ XmlTableGetValue(TableFuncScanState *state, int colnum, * CDATA sections are an exception: they don't have children * but have content in the Text/CDATA node itself. */ - node = xpathobj->nodesetval->nodeTab[0]; if (node->type != XML_CDATA_SECTION_NODE && node->type != XML_TEXT_NODE) node = node->xmlChildrenNode; -- cgit v1.2.3