Comment 2 for bug 1706514

I can confirm this is the case when log_bin is disabled, but not when it is enabled.
Interestingly, depending on table schema, either a deadlock or duplicate key error is returned.

mysql> select @@version,@@log_bin,@@log_slave_updates;
+--------------+-----------+---------------------+
| @@version | @@log_bin | @@log_slave_updates |
+--------------+-----------+---------------------+
| 5.7.18-15-57 | 0 | 0 |
+--------------+-----------+---------------------+
1 row in set (0.00 sec)

mysql> show create table B_test\G
*************************** 1. row ***************************
       Table: B_test
Create Table: CREATE TABLE `B_test` (
  `INDaa` decimal(1,0) DEFAULT NULL,
  `EUaa` decimal(1,0) DEFAULT NULL,
  `BAaa` decimal(3,0) DEFAULT NULL,
  `REKaa` decimal(10,0) NOT NULL,
  `IBaa` varchar(34) NOT NULL,
  `SALDOaa` decimal(13,2) DEFAULT NULL,
  `SALDO_aa` decimal(11,2) DEFAULT NULL,
  `SALDO_Caa` decimal(11,2) DEFAULT NULL,
  `SALDO_Vaa` decimal(13,2) DEFAULT NULL,
  `REK_SRaa` decimal(3,0) DEFAULT NULL,
  `RAPaa` decimal(2,0) DEFAULT NULL,
  `VERHaa` decimal(1,0) DEFAULT NULL,
  `ZAB` decimal(1,0) DEFAULT NULL,
  `SFIATIG` decimal(1,0) DEFAULT NULL,
  `DFIATIE_UIT` decimal(1,0) DEFAULT NULL,
  `IIV_RFTE` decimal(1,0) DEFAULT NULL,
  `INDAILEN` decimal(1,0) DEFAULT NULL,
  `DAT_TST_TRASA` decimal(8,0) DEFAULT NULL,
  `JKOM_BH_KANTF` decimal(4,0) DEFAULT NULL,
  `RDEDEN` decimal(3,0) DEFAULT NULL,
  `HEGRLD_VAAGJ` decimal(1,0) DEFAULT NULL,
  `RAT_OPENIKL` decimal(8,0) DEFAULT NULL,
  `RED_LIMIT` decimal(11,2) DEFAULT NULL,
  PRIMARY KEY (`REKaa`),
  UNIQUE KEY `BREKIBANIDX` (`IBaa`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)

mysql> load data local infile '/var/lib/mysql-files/BREK_test1.csv' into table B_test;
ERROR 1213 (40001): WSREP detected deadlock/conflict and aborted the transaction. Try restarting the transaction

Works OK with log_bin enabled:

mysql> select @@version,@@log_bin,@@log_slave_updates;
+------------------+-----------+---------------------+
| @@version | @@log_bin | @@log_slave_updates |
+------------------+-----------+---------------------+
| 5.7.18-15-57-log | 1 | 0 |
+------------------+-----------+---------------------+
1 row in set (0.00 sec)

mysql> truncate B_test;
Query OK, 0 rows affected (0.06 sec)

mysql> load data local infile '/var/lib/mysql-files/BREK_test1.csv' into table B_test;
Query OK, 17542 rows affected (1.62 sec)
Records: 17542 Deleted: 0 Skipped: 0 Warnings: 0

For a sysbench table, result different (log_bin disabled):

mysql> truncate sbtest1;
Query OK, 0 rows affected (0.03 sec)

mysql> load data local infile '/var/lib/mysql-files/sbtest1.csv' into table sbtest1;
Query OK, 5000 rows affected, 10000 warnings (0.91 sec)
Records: 15000 Deleted: 0 Skipped: 10000 Warnings: 10000

mysql> show warnings;
+---------+------+-----------------------------------------+
| Level | Code | Message |
+---------+------+-----------------------------------------+
| Warning | 1062 | Duplicate entry '2' for key 'PRIMARY' |
| Warning | 1062 | Duplicate entry '5' for key 'PRIMARY' |
| Warning | 1062 | Duplicate entry '8' for key 'PRIMARY' |
...