MDEV-13227: Assertion failure len < 16384 in file rem0rec.cc line 1285bb-10.1-MDEV-13227

Crashes with innodb_page_size=64K. Does not crash at <= 32K.

Problem was that when blob record that was earlier < 16k is
enlarged at update wo that length > 16K it should be stored
externally. However, that was not enforced when page-size = 64K
(note that 16K+1 < 64K/2 i.e. half of the btree leaf page).

btr_cur_optimistic_update: limit max record size to 16K
or in REDUNDANT row format to 16K-1.

5 files changed, 102 insertions, 8 deletions

diff --git a/mysql-test/suite/innodb/r/innodb-enlarge-blob.result b/mysql-test/suite/innodb/r/innodb-enlarge-blob.result
new file mode 100644
index 00000000000..e74e954e360
--- /dev/null
+++ b/mysql-test/suite/innodb/r/innodb-enlarge-blob.result
@@ -0,0 +1,38 @@
+CREATE TABLE t1 (a LONGTEXT) ENGINE=INNODB DEFAULT CHARSET=UTF8 ROW_FORMAT=DYNAMIC;
+SHOW WARNINGS;
+Level	Code	Message
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B');
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+SELECT * from t1;
+DROP TABLE t1;
+CREATE TABLE t1 (a LONGTEXT) ENGINE=INNODB DEFAULT CHARSET=UTF8 ROW_FORMAT=REDUNDANT;
+SHOW WARNINGS;
+Level	Code	Message
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B');
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+SELECT * from t1;
+DROP TABLE t1;
diff --git a/mysql-test/suite/innodb/t/innodb-enlarge-blob.opt b/mysql-test/suite/innodb/t/innodb-enlarge-blob.opt
new file mode 100644
index 00000000000..4c2cd9b3e3c
--- /dev/null
+++ b/mysql-test/suite/innodb/t/innodb-enlarge-blob.opt
@@ -0,0 +1,6 @@
+--innodb-file-per-table
+--innodb-file-format='Barracuda'
+--innodb-buffer-pool-size=32M
+--innodb-log-file-size=32M
+--innodb-strict-mode=OFF
+
diff --git a/mysql-test/suite/innodb/t/innodb-enlarge-blob.test b/mysql-test/suite/innodb/t/innodb-enlarge-blob.test
new file mode 100644
index 00000000000..84c23465a5c
--- /dev/null
+++ b/mysql-test/suite/innodb/t/innodb-enlarge-blob.test
@@ -0,0 +1,50 @@
+--source include/have_innodb.inc
+--source include/innodb_page_size.inc
+
+#
+# MDEV-13227: Assertion failure len < 16384 in file rem0rec.cc line 1285
+# Crashes with innodb_page_size=64K. Does not crash at <= 32K.
+#
+CREATE TABLE t1 (a LONGTEXT) ENGINE=INNODB DEFAULT CHARSET=UTF8 ROW_FORMAT=DYNAMIC;
+SHOW WARNINGS;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B');
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+# random data no output we are only interested if fails
+--disable_result_log
+SELECT * from t1;
+--enable_result_log
+DROP TABLE t1;
+
+CREATE TABLE t1 (a LONGTEXT) ENGINE=INNODB DEFAULT CHARSET=UTF8 ROW_FORMAT=REDUNDANT;
+SHOW WARNINGS;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B');
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+INSERT INTO t1 SELECT CONCAT('A', SPACE(4087), 'B') FROM t1;
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+UPDATE t1 SET a=CONCAT(a, RAND(), a);
+# random data no output we are only interested if fails
+--disable_result_log
+SELECT * from t1;
+--enable_result_log
+DROP TABLE t1;
diff --git a/storage/innobase/btr/btr0cur.cc b/storage/innobase/btr/btr0cur.cc
index 2ae6da00549..d848ee538c6 100644
--- a/storage/innobase/btr/btr0cur.cc
+++ b/storage/innobase/btr/btr0cur.cc
@@ -2316,10 +2316,10 @@ any_extern:
 		rec = page_cur_get_rec(page_cursor);
 	}
 
-	/* We limit max record size to 16k for 64k page size. */
-	if (!dict_table_is_comp(index->table)
-	    && new_rec_size > REDUNDANT_REC_MAX_DATA_SIZE) {
-		ut_ad(srv_page_size == UNIV_PAGE_SIZE_MAX);
+	/* We limit max record size to 16k even for 64k page size. */
+	if (new_rec_size >= COMPRESSED_REC_MAX_DATA_SIZE ||
+	    (!dict_table_is_comp(index->table)
+	     && new_rec_size >= REDUNDANT_REC_MAX_DATA_SIZE)) {
 		err = DB_OVERFLOW;
 
 		goto func_exit;
diff --git a/storage/xtradb/btr/btr0cur.cc b/storage/xtradb/btr/btr0cur.cc
index 6480b756f4e..1a27fd0d6ea 100644
--- a/storage/xtradb/btr/btr0cur.cc
+++ b/storage/xtradb/btr/btr0cur.cc
@@ -2466,10 +2466,10 @@ any_extern:
 		rec = page_cur_get_rec(page_cursor);
 	}
 
-	/* We limit max record size to 16k for 64k page size. */
-	if (!dict_table_is_comp(index->table)
-	    && new_rec_size > REDUNDANT_REC_MAX_DATA_SIZE) {
-		ut_ad(srv_page_size == UNIV_PAGE_SIZE_MAX);
+	/* We limit max record size to 16k even for 64k page size. */
+	if (new_rec_size >= COMPRESSED_REC_MAX_DATA_SIZE ||
+	    (!dict_table_is_comp(index->table)
+	     && new_rec_size >= REDUNDANT_REC_MAX_DATA_SIZE)) {
 		err = DB_OVERFLOW;
 
 		goto func_exit;