From: Noah Misch <noah@leadboat.com>
Date: Thu, 9 Jul 2015 00:44:21 +0000 (-0400)
Subject: Fix null pointer dereference in "\c" psql command.
X-Git-Tag: REL9_5_ALPHA2~130
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=fb990ce6c7d99d329843e5d70d4cdaf8d0825b38;p=postgresql

Fix null pointer dereference in "\c" psql command.

The psql crash happened when no current connection existed.  (The second
new check is optional given today's undocumented NULL argument handling
in PQhost() etc.)  Back-patch to 9.0 (all supported versions).
---

diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 38253fa098..467e34b1ff 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -1641,7 +1641,8 @@ do_connect(char *dbname, char *user, char *host, char *port)
 	 * positional syntax.
 	 */
 	keep_password =
-		((strcmp(user, PQuser(o_conn)) == 0) &&
+		(o_conn &&
+		 (strcmp(user, PQuser(o_conn)) == 0) &&
 		 (!host || strcmp(host, PQhost(o_conn)) == 0) &&
 		 (strcmp(port, PQport(o_conn)) == 0) &&
 		 !has_connection_string);
@@ -1768,7 +1769,8 @@ do_connect(char *dbname, char *user, char *host, char *port)
 	/* Tell the user about the new connection */
 	if (!pset.quiet)
 	{
-		if (param_is_newly_set(PQhost(o_conn), PQhost(pset.db)) ||
+		if (!o_conn ||
+			param_is_newly_set(PQhost(o_conn), PQhost(pset.db)) ||
 			param_is_newly_set(PQport(o_conn), PQport(pset.db)))
 		{
 			char	   *host = PQhost(pset.db);