On 19.09.2019 22:14, Alexander Korotkov wrote:
Pushed.
Attached patch fixes premature xs_orderbynulls[] assignment. The old value of
NULL flag, not the new, should be checked before pfree()ing the old value.
--
Nikita Glukhov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company
>From bf4ffb0c066dd55e027ed156790277c597f44e45 Mon Sep 17 00:00:00 2001
From: Nikita Glukhov <n.glu...@postgrespro.ru>
Date: Fri, 20 Sep 2019 00:07:30 +0300
Subject: [PATCH] Fix pfree()ing of index order-by distances
---
src/backend/access/index/indexam.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)
diff --git a/src/backend/access/index/indexam.c b/src/backend/access/index/indexam.c
index 442f414..3a061e5 100644
--- a/src/backend/access/index/indexam.c
+++ b/src/backend/access/index/indexam.c
@@ -869,11 +869,6 @@ index_store_float8_orderby_distances(IndexScanDesc scan, Oid *orderByTypes,
for (i = 0; i < scan->numberOfOrderBys; i++)
{
- scan->xs_orderbynulls[i] = distances[i].isnull;
-
- if (scan->xs_orderbynulls[i])
- scan->xs_orderbyvals[i] = (Datum) 0;
-
if (orderByTypes[i] == FLOAT8OID)
{
#ifndef USE_FLOAT8_BYVAL
@@ -881,7 +876,11 @@ index_store_float8_orderby_distances(IndexScanDesc scan, Oid *orderByTypes,
if (!scan->xs_orderbynulls[i])
pfree(DatumGetPointer(scan->xs_orderbyvals[i]));
#endif
- if (!scan->xs_orderbynulls[i])
+ scan->xs_orderbynulls[i] = distances[i].isnull;
+
+ if (scan->xs_orderbynulls[i])
+ scan->xs_orderbyvals[i] = (Datum) 0;
+ else
scan->xs_orderbyvals[i] = Float8GetDatum(distances[i].value);
}
else if (orderByTypes[i] == FLOAT4OID)
@@ -892,7 +891,11 @@ index_store_float8_orderby_distances(IndexScanDesc scan, Oid *orderByTypes,
if (!scan->xs_orderbynulls[i])
pfree(DatumGetPointer(scan->xs_orderbyvals[i]));
#endif
- if (!scan->xs_orderbynulls[i])
+ scan->xs_orderbynulls[i] = distances[i].isnull;
+
+ if (scan->xs_orderbynulls[i])
+ scan->xs_orderbyvals[i] = (Datum) 0;
+ else
scan->xs_orderbyvals[i] = Float4GetDatum((float4) distances[i].value);
}
else
@@ -908,6 +911,7 @@ index_store_float8_orderby_distances(IndexScanDesc scan, Oid *orderByTypes,
if (scan->xs_recheckorderby)
elog(ERROR, "ORDER BY operator must return float8 or float4 if the distance function is lossy");
scan->xs_orderbynulls[i] = true;
+ scan->xs_orderbyvals[i] = (Datum) 0;
}
}
}
--
2.7.4
