diff --git a/client/mysql_upgrade.c b/client/mysql_upgrade.c
index 617d5464e34..36c73f69716 100644
--- a/client/mysql_upgrade.c
+++ b/client/mysql_upgrade.c
@@ -1462,7 +1462,12 @@ int main(int argc, char **argv)
   open_mysql_upgrade_file();
 
   if (opt_check_upgrade)
-    exit(upgrade_already_done(0) == 0);
+  {
+    int upgrade_needed = upgrade_already_done(0);
+    free_used_memory();
+    my_end(my_end_arg);
+    exit(upgrade_needed == 0);
+  }
 
   /* Find mysqlcheck */
   find_tool(mysqlcheck_path, IF_WIN("mariadb-check.exe", "mariadb-check"), self_name);
diff --git a/mysql-test/main/mysql_upgrade_file_leak.result b/mysql-test/main/mysql_upgrade_file_leak.result
new file mode 100644
index 00000000000..648a0c97802
--- /dev/null
+++ b/mysql-test/main/mysql_upgrade_file_leak.result
@@ -0,0 +1,4 @@
+Running mysql_upgrade with --check-if-upgrade-is-needed
+Checking for absence of temporary files by mysql_upgrade
+No temporary files found
+End of 10.4 tests
diff --git a/mysql-test/main/mysql_upgrade_file_leak.test b/mysql-test/main/mysql_upgrade_file_leak.test
new file mode 100644
index 00000000000..44f178322b4
--- /dev/null
+++ b/mysql-test/main/mysql_upgrade_file_leak.test
@@ -0,0 +1,24 @@
+-- source include/mysql_upgrade_preparation.inc
+
+#
+# MDEV-31925 mysqld_upgrade --check-if-upgrade-is-needed leaks files
+#
+
+# Run mysql_upgrade with --check-if-upgrade-is-needed
+--echo Running mysql_upgrade with --check-if-upgrade-is-needed
+--exec $MYSQL_UPGRADE --check-if-upgrade-is-needed 2>&1
+
+# Check if temporary files related to mysql_upgrade are cleared
+--echo Checking for absence of temporary files by mysql_upgrade
+--perl
+
+# Use the temporary directory path from the MySQL configuration
+my $tmpdir = "$ENV{MYSQL_TMP_DIR}";
+
+die "Test failed: Found temporary file left by mysql_upgrade\n" if (glob("$tmpdir/mysql_upgrade-*"));
+print "No temporary files found\n";
+EOF
+
+let $MYSQLD_DATADIR= `select @@datadir`;
+--remove_file $MYSQLD_DATADIR/mysql_upgrade_info
+--echo End of 10.4 tests
diff --git a/mysql-test/suite/binlog_encryption/rpl_gtid_basic.result b/mysql-test/suite/binlog_encryption/rpl_gtid_basic.result
index 5771b0f405f..99721813159 100644
--- a/mysql-test/suite/binlog_encryption/rpl_gtid_basic.result
+++ b/mysql-test/suite/binlog_encryption/rpl_gtid_basic.result
@@ -182,6 +182,13 @@ BINLOG_GTID_POS('master-bin.000001',18446744073709551616)
 NULL
 Warnings:
 Warning	1916	Got overflow when converting '18446744073709551616' to INT. Value truncated
+SET sql_log_bin= 0;
+CREATE TABLE t1 AS SELECT MASTER_POS_WAIT(@binlog_file, 4, 0);
+SELECT BINLOG_GTID_POS(@binlog_file, 4);
+BINLOG_GTID_POS(@binlog_file, 4)
+NULL
+DROP TABLE t1;
+SET sql_log_bin= 1;
 *** Some tests of @@GLOBAL.gtid_binlog_state ***
 connection server_2;
 include/sync_with_master_gtid.inc
diff --git a/mysql-test/suite/rpl/r/rpl_gtid_basic.result b/mysql-test/suite/rpl/r/rpl_gtid_basic.result
index aefb80a7c13..afc700a72c5 100644
--- a/mysql-test/suite/rpl/r/rpl_gtid_basic.result
+++ b/mysql-test/suite/rpl/r/rpl_gtid_basic.result
@@ -182,6 +182,13 @@ BINLOG_GTID_POS('master-bin.000001',18446744073709551616)
 NULL
 Warnings:
 Warning	1916	Got overflow when converting '18446744073709551616' to INT. Value truncated
+SET sql_log_bin= 0;
+CREATE TABLE t1 AS SELECT MASTER_POS_WAIT(@binlog_file, 4, 0);
+SELECT BINLOG_GTID_POS(@binlog_file, 4);
+BINLOG_GTID_POS(@binlog_file, 4)
+NULL
+DROP TABLE t1;
+SET sql_log_bin= 1;
 *** Some tests of @@GLOBAL.gtid_binlog_state ***
 connection server_2;
 include/sync_with_master_gtid.inc
diff --git a/mysql-test/suite/rpl/t/rpl_gtid_basic.test b/mysql-test/suite/rpl/t/rpl_gtid_basic.test
index 70bd0087f7a..a7af234d47e 100644
--- a/mysql-test/suite/rpl/t/rpl_gtid_basic.test
+++ b/mysql-test/suite/rpl/t/rpl_gtid_basic.test
@@ -162,6 +162,13 @@ eval SELECT BINLOG_GTID_POS('$valid_binlog_name',0);
 eval SELECT BINLOG_GTID_POS('$valid_binlog_name',18446744073709551615);
 eval SELECT BINLOG_GTID_POS('$valid_binlog_name',18446744073709551616);
 
+# MDEV-33045: Server crashes in Item_func_binlog_gtid_pos::val_str / Binary_string::c_ptr_safe
+SET sql_log_bin= 0;
+CREATE TABLE t1 AS SELECT MASTER_POS_WAIT(@binlog_file, 4, 0);
+SELECT BINLOG_GTID_POS(@binlog_file, 4);
+DROP TABLE t1;
+SET sql_log_bin= 1;
+
 
 --echo *** Some tests of @@GLOBAL.gtid_binlog_state ***
 --connection server_2
diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc
index 093e38c00c9..cedbace52ca 100644
--- a/sql/item_strfunc.cc
+++ b/sql/item_strfunc.cc
@@ -3213,12 +3213,12 @@ String *Item_func_binlog_gtid_pos::val_str(String *str)
   String name_str, *name;
   longlong pos;
 
-  if (args[0]->null_value || args[1]->null_value)
-    goto err;
-
   name= args[0]->val_str(&name_str);
   pos= args[1]->val_int();
 
+  if (args[0]->null_value || args[1]->null_value)
+    goto err;
+
   if (pos < 0 || pos > UINT_MAX32)
     goto err;
 
diff --git a/sql/rpl_parallel.cc b/sql/rpl_parallel.cc
index c04883c2906..15d6ab77bbc 100644
--- a/sql/rpl_parallel.cc
+++ b/sql/rpl_parallel.cc
@@ -862,8 +862,7 @@ do_retry:
     thd->wait_for_commit_ptr->unregister_wait_for_prior_commit();
   DBUG_EXECUTE_IF("inject_mdev8031", {
       /* Simulate that we get deadlock killed at this exact point. */
-      rgi->killed_for_retry= rpl_group_info::RETRY_KILL_KILLED;
-      thd->set_killed(KILL_CONNECTION);
+      slave_background_kill_request(thd);
   });
 #ifdef ENABLED_DEBUG_SYNC
   DBUG_EXECUTE_IF("rpl_parallel_simulate_wait_at_retry", {
@@ -2567,8 +2566,10 @@ rpl_parallel::stop_during_until()
 bool
 rpl_parallel::workers_idle(Relay_log_info *rli)
 {
-  return rli->last_inuse_relaylog->queued_count ==
-         rli->last_inuse_relaylog->dequeued_count;
+  mysql_mutex_assert_owner(&rli->data_lock);
+  return !rli->last_inuse_relaylog ||
+    rli->last_inuse_relaylog->queued_count ==
+    rli->last_inuse_relaylog->dequeued_count;
 }
 
 
diff --git a/sql/slave.cc b/sql/slave.cc
index 4075d270e68..d22b983443b 100644
--- a/sql/slave.cc
+++ b/sql/slave.cc
@@ -5426,19 +5426,25 @@ pthread_handler_t handle_slave_sql(void *arg)
   }
   else
     rli->gtid_skip_flag = GTID_SKIP_NOT;
+  mysql_mutex_lock(&rli->data_lock);
   if (init_relay_log_pos(rli,
                          rli->group_relay_log_name,
                          rli->group_relay_log_pos,
-                         1 /*need data lock*/, &errmsg,
+                         0 /*need data lock*/, &errmsg,
                          1 /*look for a description_event*/))
   { 
     rli->report(ERROR_LEVEL, ER_SLAVE_FATAL_ERROR, NULL,
                 "Error initializing relay log position: %s", errmsg);
+    mysql_mutex_unlock(&rli->data_lock);
     goto err_before_start;
   }
   rli->reset_inuse_relaylog();
   if (rli->alloc_inuse_relaylog(rli->group_relay_log_name))
+  {
+    mysql_mutex_unlock(&rli->data_lock);
     goto err_before_start;
+  }
+  mysql_mutex_unlock(&rli->data_lock);
 
   strcpy(rli->future_event_master_log_name, rli->group_master_log_name);
   THD_CHECK_SENTRY(thd);