MDEV-24978 crash with transaction on table with no PK and long fullte…

…xt column If a table has no unique indexes, write set key information will be collected on all columns in the table. The write set key information has space only for max 3500 bytes for individual column, and if a varchar colummn of such non-primary key table is longer than this limit, currently a crash follows. The fix in this commit, is to truncate key values extracted from such long varhar columns to max 3500 bytes. This may potentially lead to false positive certification failures for transactions, which operate on separate cluster nodes, and update/insert/delete table rows, which differ only in the part of such long columns after 3500 bytes border. Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
MariaDB · Sep 30, 2021 · d5a15f0 · d5a15f0
1 parent b2a5e0f
commit d5a15f0
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diff --git a/mysql-test/suite/galera/r/galera_fulltext.result b/mysql-test/suite/galera/r/galera_fulltext.result
@@ -34,3 +34,59 @@ COUNT(f1) = 1000
 1
 DROP TABLE t1;
 DROP TABLE ten;
+connection node_1;
+SET @value=REPEAT (1,5001);
+CREATE TABLE t (a VARCHAR(5000),FULLTEXT (a)) engine=innodb;
+INSERT IGNORE INTO t VALUES(@value);
+Warnings:
+Warning	1265	Data truncated for column 'a' at row 1
+SELECT COUNT(*) FROM t;
+COUNT(*)
+1
+connection node_2;
+SELECT COUNT(*) FROM t;
+COUNT(*)
+1
+connection node_1;
+DROP TABLE t;
+CREATE TABLE t (a VARCHAR(5000)) engine=innodb;
+INSERT IGNORE INTO t VALUES(@value);
+Warnings:
+Warning	1265	Data truncated for column 'a' at row 1
+SELECT COUNT(*) FROM t;
+COUNT(*)
+1
+connection node_2;
+SELECT COUNT(*) FROM t;
+COUNT(*)
+1
+connection node_1;
+DROP TABLE t;
+connection node_1;
+SET @value=REPEAT (1,5001);
+CREATE TABLE t (a VARCHAR(5000),FULLTEXT (a)) engine=innodb DEFAULT CHARSET=utf8;
+INSERT IGNORE INTO t VALUES(@value);
+Warnings:
+Warning	1265	Data truncated for column 'a' at row 1
+SELECT COUNT(*) FROM t;
+COUNT(*)
+1
+connection node_2;
+SELECT COUNT(*) FROM t;
+COUNT(*)
+1
+connection node_1;
+DROP TABLE t;
+CREATE TABLE t (a VARCHAR(5000)) engine=innodb DEFAULT CHARSET=utf8;
+INSERT IGNORE INTO t VALUES(@value);
+Warnings:
+Warning	1265	Data truncated for column 'a' at row 1
+SELECT COUNT(*) FROM t;
+COUNT(*)
+1
+connection node_2;
+SELECT COUNT(*) FROM t;
+COUNT(*)
+1
+connection node_1;
+DROP TABLE t;
diff --git a/mysql-test/suite/galera/t/galera_fulltext.test b/mysql-test/suite/galera/t/galera_fulltext.test
@@ -58,28 +58,50 @@ SELECT COUNT(f1) = 1000 FROM t1 WHERE MATCH(f1) AGAINST ('abcdefjhk');
 
 DROP TABLE t1;
 DROP TABLE ten;
-
-#
-# Case 2: UTF-8
-# TODO: MDEV-24978
 #
-#--connection node_1
-#SET @value=REPEAT (1,5001);
-#CREATE TABLE t (a VARCHAR(5000),FULLTEXT (a)) engine=innodb DEFAULT CHARSET=utf8;
-#INSERT IGNORE INTO t VALUES(@value);
-#SELECT COUNT(*) FROM t;
+# MDEV-24978 : SIGABRT in __libc_message
 #
-#--connection node_2
-#SELECT COUNT(*) FROM t;
-#
-#--connection node_1
-#DROP TABLE t;
-#CREATE TABLE t (a VARCHAR(5000)) engine=innodb DEFAULT CHARSET=utf8;
-#INSERT IGNORE INTO t VALUES(@value);
-#SELECT COUNT(*) FROM t;
+--connection node_1
+SET @value=REPEAT (1,5001);
+CREATE TABLE t (a VARCHAR(5000),FULLTEXT (a)) engine=innodb;
+INSERT IGNORE INTO t VALUES(@value);
+SELECT COUNT(*) FROM t;
+
+--connection node_2
+SELECT COUNT(*) FROM t;
+
+--connection node_1
+DROP TABLE t;
+CREATE TABLE t (a VARCHAR(5000)) engine=innodb;
+INSERT IGNORE INTO t VALUES(@value);
+SELECT COUNT(*) FROM t;
+
+--connection node_2
+SELECT COUNT(*) FROM t;
+
+--connection node_1
+DROP TABLE t;
+
 #
-#--connection node_2
-#SELECT COUNT(*) FROM t;
+# Case 2: UTF-8
 #
-#--connection node_1
-#DROP TABLE t;
+--connection node_1
+SET @value=REPEAT (1,5001);
+CREATE TABLE t (a VARCHAR(5000),FULLTEXT (a)) engine=innodb DEFAULT CHARSET=utf8;
+INSERT IGNORE INTO t VALUES(@value);
+SELECT COUNT(*) FROM t;
+
+--connection node_2
+SELECT COUNT(*) FROM t;
+
+--connection node_1
+DROP TABLE t;
+CREATE TABLE t (a VARCHAR(5000)) engine=innodb DEFAULT CHARSET=utf8;
+INSERT IGNORE INTO t VALUES(@value);
+SELECT COUNT(*) FROM t;
+
+--connection node_2
+SELECT COUNT(*) FROM t;
+
+--connection node_1
+DROP TABLE t;
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
@@ -7218,10 +7218,14 @@ wsrep_store_key_val_for_row(
 
 			/* In a column prefix index, we may need to truncate
 			the stored value: */
-
 			if (true_len > key_len) {
 				true_len = key_len;
 			}
+			/* cannot exceed max column lenght either, we may need to truncate
+			the stored value: */
+			if (true_len > sizeof(sorted)) {
+			  true_len = sizeof(sorted);
+			}
 
 			memcpy(sorted, data, true_len);
 			true_len = wsrep_innobase_mysql_sort(
@@ -7234,8 +7238,8 @@ wsrep_store_key_val_for_row(
 				actual data. The rest of the space was reset to zero
 				in the bzero() call above. */
 				if (true_len > buff_space) {
-					fprintf (stderr,
-						 "WSREP: key truncated: %s\n",
+					WSREP_DEBUG (
+						 "write set key truncated for: %s\n",
 						 wsrep_thd_query(thd));
 					true_len = buff_space;
 				}