Fix minor memory leak in Standby startup

StandbyRecoverPreparedTransactions() leaked the buffer
used for two phase state file. This was leaked once
at startup and at every shutdown checkpoint seen.

Backpatch to 9.6

Stas Kelvich

1 files changed, 2 insertions, 0 deletions

diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index 9f55adcaf5e..1323fb508dc 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -1886,6 +1886,8 @@ StandbyRecoverPreparedTransactions(bool overwriteOK)
 				Assert(TransactionIdFollows(subxid, xid));
 				SubTransSetParent(xid, subxid, overwriteOK);
 			}
+
+			pfree(buf);
 		}
 	}
 	FreeDir(cldir);