From 57641a165ffa7ef33c21c321a59104db7985df74 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue, 3 Aug 2010 00:10:39 +0000
Subject: [PATCH] Fix core dump in QTNodeCompare when tsquery_cmp() is applied
 to two empty tsqueries.  CompareTSQ has to have a guard for the case rather
 than blindly applying QTNodeCompare to random data past the end of the
 datums.  Also, change QTNodeCompare to be a little less trusting: use an
 actual test rather than just Assert'ing that the input is sane.  Problem
 encountered while investigating another issue (I saw a core dump in
 autoanalyze on a table containing multiple empty tsquery values).

Back-patch to all branches with tsquery support.

In HEAD, also fix some bizarre (though not outright wrong) coding in
tsq_mcontains().
---
 src/backend/utils/adt/tsquery_op.c   | 16 ++++++++--------
 src/backend/utils/adt/tsquery_util.c | 11 +++++++----
 2 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/backend/utils/adt/tsquery_op.c b/src/backend/utils/adt/tsquery_op.c
index 2b453e0286..0b81ff5938 100644
--- a/src/backend/utils/adt/tsquery_op.c
+++ b/src/backend/utils/adt/tsquery_op.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/tsquery_op.c,v 1.8 2010/01/02 16:57:55 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/tsquery_op.c,v 1.9 2010/08/03 00:10:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -149,7 +149,7 @@ CompareTSQ(TSQuery a, TSQuery b)
 	{
 		return (VARSIZE(a) < VARSIZE(b)) ? -1 : 1;
 	}
-	else
+	else if (a->size != 0)
 	{
 		QTNode	   *an = QT2QTN(GETQUERY(a), GETOPERAND(a));
 		QTNode	   *bn = QT2QTN(GETQUERY(b), GETOPERAND(b));
@@ -247,20 +247,20 @@ tsq_mcontains(PG_FUNCTION_ARGS)
 		PG_RETURN_BOOL(false);
 	}
 
+	iq = GETQUERY(query);
 	ie = GETQUERY(ex);
 
 	for (i = 0; i < ex->size; i++)
 	{
-		iq = GETQUERY(query);
 		if (ie[i].type != QI_VAL)
 			continue;
 		for (j = 0; j < query->size; j++)
-			if (iq[j].type == QI_VAL && ie[i].qoperand.valcrc == iq[j].qoperand.valcrc)
-			{
-				j = query->size + 1;
+		{
+			if (iq[j].type == QI_VAL &&
+				ie[i].qoperand.valcrc == iq[j].qoperand.valcrc)
 				break;
-			}
-		if (j == query->size)
+		}
+		if (j >= query->size)
 		{
 			PG_FREE_IF_COPY(query, 0);
 			PG_FREE_IF_COPY(ex, 1);
diff --git a/src/backend/utils/adt/tsquery_util.c b/src/backend/utils/adt/tsquery_util.c
index ce8a892639..5e309fea7c 100644
--- a/src/backend/utils/adt/tsquery_util.c
+++ b/src/backend/utils/adt/tsquery_util.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/tsquery_util.c,v 1.13 2010/01/02 16:57:55 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/tsquery_util.c,v 1.14 2010/08/03 00:10:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -113,13 +113,11 @@ QTNodeCompare(QTNode *an, QTNode *bn)
 		}
 		return 0;
 	}
-	else
+	else if (an->valnode->type == QI_VAL)
 	{
 		QueryOperand *ao = &an->valnode->qoperand;
 		QueryOperand *bo = &bn->valnode->qoperand;
 
-		Assert(an->valnode->type == QI_VAL);
-
 		if (ao->valcrc != bo->valcrc)
 		{
 			return (ao->valcrc > bo->valcrc) ? -1 : 1;
@@ -127,6 +125,11 @@ QTNodeCompare(QTNode *an, QTNode *bn)
 
 		return tsCompareString(an->word, ao->length, bn->word, bo->length, false);
 	}
+	else
+	{
+		elog(ERROR, "unrecognized QueryItem type: %d", an->valnode->type);
+		return 0;				/* keep compiler quiet */
+	}
 }
 
 static int