From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 8 Feb 2019 18:30:42 +0000 (-0500)
Subject: Defend against null error message reported by libxml2.
X-Git-Tag: REL_12_BETA1~784
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=0edef16d76beb8286cc832e4e1daf1f16b3d8f4a;p=postgresql

Defend against null error message reported by libxml2.

While this isn't really supposed to happen, it can occur in OOM
situations and perhaps others.  Instead of crashing, substitute
"(no message provided)".

I didn't worry about localizing this text, since we aren't
localizing anything else here; besides, if we're on the edge of
OOM, it's unlikely gettext() would work.

Report and fix by Sergio Conde Gómez in bug #15624.

Discussion: https://postgr.es/m/15624-4dea54091a2864e6@postgresql.org
---

diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index 11a5d706fd..f36aab899a 100644
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -1697,7 +1697,10 @@ xml_errorHandler(void *data, xmlErrorPtr error)
 		appendStringInfo(errorBuf, "line %d: ", error->line);
 	if (name != NULL)
 		appendStringInfo(errorBuf, "element %s: ", name);
-	appendStringInfoString(errorBuf, error->message);
+	if (error->message != NULL)
+		appendStringInfoString(errorBuf, error->message);
+	else
+		appendStringInfoString(errorBuf, "(no message provided)");
 
 	/*
 	 * Append context information to errorBuf.