Initialize dblink remoteConn struct in all cases

Two of the members of rconn were left uninitialized. When
dblink_open() is called without an outer transaction it
handles the initialization for us, but with an outer
transaction it does not. Arrange for initialization
in all cases. Backpatch to all supported versions.

Reported-by: Alexander Lakhin
Discussion: https://www.postgresql.org/message-id/flat/9bd0744f-5f04-c778-c5b3-809efe9c30c7%40joeconway.com#c545909a41664991aca60c4d70a10ce7

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index 9528d33f4849db3c2eaf7407ee60a9c01cbeaf79..ad69a53e556846d5de86bdf042eeb937d28d07ab 100644 (file)
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -263,8 +263,13 @@ dblink_connect(PG_FUNCTION_ARGS)
                conname_or_str = text_to_cstring(PG_GETARG_TEXT_PP(0));
 
        if (connname)
+       {
                rconn = (remoteConn *) MemoryContextAlloc(TopMemoryContext,
                                                                                                  sizeof(remoteConn));
+               rconn->conn = NULL;
+               rconn->openCursorCount = 0;
+               rconn->newXactForCursor = false;
+       }
 
        /* first check for valid foreign data server */
        connstr = get_connect_string(conname_or_str);