From: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Date: Tue, 2 Aug 2011 07:47:17 +0000 (+0300)
Subject: Avoid integer overflow when LIMIT + OFFSET >= 2^63.
X-Git-Url: http://git.postgresql.org/gitweb/?a=commitdiff_plain;h=refs%2Fheads%2FREL8_3_STABLE;p=users%2Fc2main%2Fpostgres.git

Avoid integer overflow when LIMIT + OFFSET >= 2^63.

This fixes bug #6139 reported by Hitoshi Harada.
---

diff --git a/src/backend/executor/nodeLimit.c b/src/backend/executor/nodeLimit.c
index 1755268211..7e0b98211f 100644
--- a/src/backend/executor/nodeLimit.c
+++ b/src/backend/executor/nodeLimit.c
@@ -125,7 +125,7 @@ ExecLimit(LimitState *node)
 				 * the state machine state to record having done so.
 				 */
 				if (!node->noCount &&
-					node->position >= node->offset + node->count)
+					node->position - node->offset >= node->count)
 				{
 					node->lstate = LIMIT_WINDOWEND;
 					return NULL;