pg_upgrade: Fix inconsistency in memory freeing

michaelpq · RanierV · michaelpq · commit ee78823ff5f6 · 2025-02-28T10:15:32.000+09:00
The function in charge of freeing the memory from a result created by PQescapeIdentifier() has to be PQfreemem(), to ensure that both allocation and free come from libpq. One spot in pg_upgrade was not respecting that for pg_database's datlocale (daticulocale in v16) when the collation provider is libc (aka datlocale/daticulocale is NULL) with an allocation done using pg_strdup() and a free with PQfreemem(). The code is changed to always use PQescapeLiteral() when processing the input. Oversight in 9637bad. This commit is similar to 48e4ae9 and 5b94e27. Author: Michael Paquier <michael@paquier.xyz> Co-authored-by: Ranier Vilela <ranier.vf@gmail.com> Discussion: https://postgr.es/m/Z601RQxTmIUohdkV@paquier.xyz Backpatch-through: 16
diff --git a/src/bin/pg_upgrade/pg_upgrade.c b/src/bin/pg_upgrade/pg_upgrade.c
@@ -408,6 +408,7 @@ set_locale_and_encoding(void)
 	char	   *datcollate_literal;
 	char	   *datctype_literal;
 	char	   *datlocale_literal = NULL;
+	char	   *datlocale_src;
 	DbLocaleInfo *locale = old_cluster.template0;
 
 	prep_status("Setting locale and encoding for new cluster");
@@ -421,12 +422,10 @@ set_locale_and_encoding(void)
 	datctype_literal = PQescapeLiteral(conn_new_template1,
 									   locale->db_ctype,
 									   strlen(locale->db_ctype));
-	if (locale->db_locale)
-		datlocale_literal = PQescapeLiteral(conn_new_template1,
-											locale->db_locale,
-											strlen(locale->db_locale));
-	else
-		datlocale_literal = pg_strdup("NULL");
+	datlocale_src = locale->db_locale ? locale->db_locale : "NULL";
+	datlocale_literal = PQescapeLiteral(conn_new_template1,
+										datlocale_src,
+										strlen(datlocale_src));
 
 	/* update template0 in new cluster */
 	if (GET_MAJOR_VERSION(new_cluster.major_version) >= 1700)
