MDEV-31928 Assertion xid ... < 128 failed in trx_undo_write_xid()

trx_undo_write_xid(): Correct an off-by-one error in a debug assertion.

mysql-test/suite/innodb/r/innodb-xa.result

@@ -15,3 +15,30 @@ xa prepare 'xid2';
 release savepoint `sv1`;
 xa commit 'xid2';
 drop table t1;
+#
+# MDEV-31928 Assertion xid ... < 128 failed in trx_undo_write_xid()
+#
+CREATE TABLE t (a INT PRIMARY KEY) ENGINE=INNODB;
+XA START 'gtrid_67890123456789012345678901234567890123456789012345678901234','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '1234567890' at line 1
+XA START 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_67890123456789012345678901234567890123456789012345678901234',1234567890;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '1234567890' at line 1
+XA START 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+INSERT INTO t VALUES(1);
+XA END 'gtrid_67890123456789012345678901234567890123456789012345678901234','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '1234567890' at line 1
+XA END 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_67890123456789012345678901234567890123456789012345678901234',1234567890;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '1234567890' at line 1
+XA END 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+XA PREPARE 'gtrid_67890123456789012345678901234567890123456789012345678901234','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '1234567890' at line 1
+XA PREPARE 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_67890123456789012345678901234567890123456789012345678901234',1234567890;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '1234567890' at line 1
+XA PREPARE 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+XA COMMIT 'gtrid_67890123456789012345678901234567890123456789012345678901234','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '1234567890' at line 1
+XA COMMIT 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_67890123456789012345678901234567890123456789012345678901234',1234567890;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '1234567890' at line 1
+XA COMMIT 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+DROP TABLE t;
+# End of 10.4 tests

mysql-test/suite/innodb/t/innodb-xa.test

 --source include/have_innodb.inc
 
---disable_abort_on_error
+--error ER_XAER_NOTA
 xa rollback 'xid2';
 drop table if exists t1;
 create table t1(a int)engine=innodb;
@@ -9,9 +9,42 @@ xa start 'xid2';
 insert into `t1` values (1);
 savepoint `sv1`;
 xa end 'xid2';
+--error ER_XAER_RMFAIL
 start transaction;
 xa prepare 'xid2';
 release savepoint `sv1`;
 xa commit 'xid2';
 drop table t1;
 
+-- echo #
+-- echo # MDEV-31928 Assertion xid ... < 128 failed in trx_undo_write_xid()
+-- echo #
+
+CREATE TABLE t (a INT PRIMARY KEY) ENGINE=INNODB;
+--error ER_PARSE_ERROR
+XA START 'gtrid_67890123456789012345678901234567890123456789012345678901234','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+--error ER_PARSE_ERROR
+XA START 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_67890123456789012345678901234567890123456789012345678901234',1234567890;
+XA START 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+
+INSERT INTO t VALUES(1);
+
+--error ER_PARSE_ERROR
+XA END 'gtrid_67890123456789012345678901234567890123456789012345678901234','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+--error ER_PARSE_ERROR
+XA END 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_67890123456789012345678901234567890123456789012345678901234',1234567890;
+XA END 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+--error ER_PARSE_ERROR
+XA PREPARE 'gtrid_67890123456789012345678901234567890123456789012345678901234','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+--error ER_PARSE_ERROR
+XA PREPARE 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_67890123456789012345678901234567890123456789012345678901234',1234567890;
+XA PREPARE 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+--error ER_PARSE_ERROR
+XA COMMIT 'gtrid_67890123456789012345678901234567890123456789012345678901234','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+--error ER_PARSE_ERROR
+XA COMMIT 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_67890123456789012345678901234567890123456789012345678901234',1234567890;
+XA COMMIT 'gtrid_6789012345678901234567890123456789012345678901234567890123','bqual_6789012345678901234567890123456789012345678901234567890123',1234567890;
+
+DROP TABLE t;
+
+-- echo # End of 10.4 tests

storage/innobase/trx/trx0undo.cc

@@ -665,7 +665,7 @@ trx_undo_write_xid(
 {
 	DBUG_ASSERT(xid->gtrid_length >= 0);
 	DBUG_ASSERT(xid->bqual_length >= 0);
-	DBUG_ASSERT(xid->gtrid_length + xid->bqual_length < XIDDATASIZE);
+	DBUG_ASSERT(xid->gtrid_length + xid->bqual_length <= XIDDATASIZE);
 
 	mlog_write_ulint(log_hdr + TRX_UNDO_XA_FORMAT,
 			 static_cast<ulint>(xid->formatID),