From f390f70af004f25ab43c54862d728cbcb57e1966 Mon Sep 17 00:00:00 2001
From: Tatsuo Ishii <ishii@postgresql.org>
Date: Tue, 20 Dec 2016 11:38:12 +0900
Subject: [PATCH] Fix occasional segfault when query cache is enabled.

Per bug 263.
---
 src/query_cache/pool_memqcache.c | 2 ++
 src/utils/mmgr/mcxt.c            | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/src/query_cache/pool_memqcache.c b/src/query_cache/pool_memqcache.c
index 06ce6b9da..b78169325 100644
--- a/src/query_cache/pool_memqcache.c
+++ b/src/query_cache/pool_memqcache.c
@@ -3089,6 +3089,8 @@ static void pool_check_and_discard_cache_buffer(int num_oids, int *oids)
 			continue;
 
 		soids = (int *)pool_get_buffer(cache->oids, &len);
+		if (!soids || !len)
+			continue;
 
 		for(j=0;j<cache->num_oids;j++)
 		{
diff --git a/src/utils/mmgr/mcxt.c b/src/utils/mmgr/mcxt.c
index a1a490f36..0eae52012 100644
--- a/src/utils/mmgr/mcxt.c
+++ b/src/utils/mmgr/mcxt.c
@@ -703,6 +703,9 @@ pfree(void *pointer)
 	Assert(pointer != NULL);
 	Assert(pointer == (void *) MAXALIGN(pointer));
 
+	if (pointer == NULL)
+		return;
+
 	/*
 	 * OK, it's probably safe to look at the chunk header.
 	 */
-- 
2.39.5