From ba6968fc79c36aa4299cf082a25b8fd0877b2060 Mon Sep 17 00:00:00 2001
From: Florian Schmaus <flo@geekplace.eu>
Date: Wed, 3 Mar 2021 21:41:07 +0100
Subject: [PATCH] [xmlparser-stax] Fix potential IAE in
 StaxXmlPullParser.getNamespace()

StAX's NamespaceContext.getNamespaceURI(String) is allowed to throw an
IllegalArgumentException in case the argument is null. We simply
re-use getNamespace(String) which will substitute the default
namespace if the argument is null to avoid this.

Connection closed due to an exception
java.lang.IllegalArgumentException: Illegal to pass null as argument
at com.ctc.wstx.sr.NsInputElementStack.getNamespaceURI(NsInputElementStack.java:486)
at org.jivesoftware.smack.xml.stax.StaxXmlPullParser.getNamespace(StaxXmlPullParser.java:113)
at org.jivesoftware.smack.AbstractXMPPConnection.parseFeatures(AbstractXMPPConnection.java:1852)
at org.jivesoftware.smack.AbstractXMPPConnection.parseFeaturesAndNotify(AbstractXMPPConnection.java:1887)
at org.jivesoftware.smack.tcp.XMPPTCPConnection.access$1300(XMPPTCPConnection.java:130)
at org.jivesoftware.smack.tcp.XMPPTCPConnection$PacketReader.parsePackets(XMPPTCPConnection.java:983)
at org.jivesoftware.smack.tcp.XMPPTCPConnection$PacketReader.access$700(XMPPTCPConnection.java:913)
at org.jivesoftware.smack.tcp.XMPPTCPConnection$PacketReader$1.run(XMPPTCPConnection.java:936)
at java.lang.Thread.run(Thread.java:748)

Fixes SMACK-903
---
 .../org/jivesoftware/smack/xml/stax/StaxXmlPullParser.java     | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/smack-xmlparser-stax/src/main/java/org/jivesoftware/smack/xml/stax/StaxXmlPullParser.java b/smack-xmlparser-stax/src/main/java/org/jivesoftware/smack/xml/stax/StaxXmlPullParser.java
index 56542fc97..10f3453eb 100644
--- a/smack-xmlparser-stax/src/main/java/org/jivesoftware/smack/xml/stax/StaxXmlPullParser.java
+++ b/smack-xmlparser-stax/src/main/java/org/jivesoftware/smack/xml/stax/StaxXmlPullParser.java
@@ -108,9 +108,8 @@ public final class StaxXmlPullParser implements XmlPullParser {
 
     @Override
     public String getNamespace() {
-        NamespaceContext namespaceContext = xmlStreamReader.getNamespaceContext();
         String prefix = getPrefix();
-        return namespaceContext.getNamespaceURI(prefix);
+        return getNamespace(prefix);
     }
 
     @Override