MDEV-17968 Error 174 "Fatal error during initialization of handler" from...

MDEV-17968 Error 174 "Fatal error during initialization of handler" from storage engine Aria upon DELETE from partitioned table

mysql-test/main/type_timestamp.result

@@ -1129,5 +1129,19 @@ Warnings:
 Warning	1292	Truncated incorrect datetime value: 'N/A'
 DROP TABLE t1;
 #
+# MDEV-17972 Assertion `is_valid_value_slow()' failed in Datetime::Datetime
+#
+SET time_zone='+00:00';
+CREATE TABLE t1 (a TIMESTAMP(6)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES ('2001-01-01 10:20:30');
+FLUSH TABLES;
+MYD
+FF77777777FFFFFF
+SELECT a, CAST(a AS DATETIME) AS dt0, CAST(a AS DATETIME(6)) AS dt6 FROM t1;
+a	dt0	dt6
+2033-07-07 03:01:11.999999	2033-07-07 03:01:11	2033-07-07 03:01:11.999999
+DROP TABLE t1;
+SET time_zone=DEFAULT;
+#
 # End of 10.4 tests
 #

mysql-test/main/type_timestamp.test

@@ -718,6 +718,28 @@ INSERT INTO t1 VALUES (1,'2018-06-19 00:00:00');
 SELECT NULLIF(b, 'N/A') AS f, MAX(a) FROM t1 GROUP BY f;
 DROP TABLE t1;
 
+--echo #
+--echo # MDEV-17972 Assertion `is_valid_value_slow()' failed in Datetime::Datetime
+--echo #
+
+let $MYSQLD_DATADIR= `select @@datadir`;
+SET time_zone='+00:00';
+CREATE TABLE t1 (a TIMESTAMP(6)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES ('2001-01-01 10:20:30');
+FLUSH TABLES;
+--remove_file $MYSQLD_DATADIR/test/t1.MYD
+--disable_query_log
+# Write a data file with one record:
+# 0xFF       - record flags
+# 0x77777777 - TIMESTAMP integer part
+# 0xFFFFFF   - TIMESTAMP bad fractional part
+--eval SELECT CONCAT(0xFF,0x77777777,0xFFFFFF) INTO OUTFILE '$MYSQLD_DATADIR/test/t1.MYD' FIELDS TERMINATED BY '' ESCAPED BY '' LINES TERMINATED BY ''
+--eval SELECT HEX(LOAD_FILE('$MYSQLD_DATADIR/test/t1.MYD')) AS MYD
+--enable_query_log
+SELECT a, CAST(a AS DATETIME) AS dt0, CAST(a AS DATETIME(6)) AS dt6 FROM t1;
+DROP TABLE t1;
+SET time_zone=DEFAULT;
+
 --echo #
 --echo # End of 10.4 tests
 --echo #

sql/compat56.cc

@@ -20,6 +20,19 @@
 #include "myisampack.h"
 #include "my_time.h"
 
+
+static uint my_max_usec_value[7]
+{
+  0,
+  900000,
+  990000,
+  999000,
+  999900,
+  999990,
+  999999
+};
+
+
 /*** MySQL56 TIME low-level memory and disk representation routines ***/
 
 /*
@@ -397,19 +410,21 @@ void my_timestamp_from_binary(struct timeval *tm, const uchar *ptr, uint dec)
     case 0:
     default:
       tm->tv_usec= 0;
-      break;
+      return;
     case 1:
     case 2:
       tm->tv_usec= ((int) ptr[4]) * 10000;
       break;
     case 3:
     case 4:
-      tm->tv_usec= mi_sint2korr(ptr + 4) * 100;
+      tm->tv_usec= (uint) mi_uint2korr(ptr + 4) * 100;
       break;
     case 5:
     case 6:
-      tm->tv_usec= mi_sint3korr(ptr + 4);
+      tm->tv_usec= (uint) mi_uint3korr(ptr + 4);
   }
+  // The binary data my be corrupt. Cut fractional seconds to the valid range.
+  set_if_smaller(tm->tv_usec, my_max_usec_value[dec]);
 }