Bug #28825617 ASSERTION FAILURE: LOB0LOB.CC.*TRX == NULLPTR || TRX->IS_READ_UNCOMMITTED()

Post push fix.  Adding a test case.  Also fixing doxygen errors.

Author: gurusami

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

@@ -0,0 +1,49 @@
+#
+# Bug #28825617 ASSERTION FAILURE: LOB0LOB.CC.*TRX == NULLPTR
+# || TRX->IS_READ_UNCOMMITTED()
+#
+CREATE TABLE t1 (a INT PRIMARY KEY, b TEXT, c TEXT, INDEX (b(1)));
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) NOT NULL,
+  `b` text,
+  `c` text,
+  PRIMARY KEY (`a`),
+  KEY `b` (`b`(1))
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
+# Connection con1:
+INSERT INTO t1 (a, b, c) VALUES (1, 'hello', repeat('blob ', 12345));
+BEGIN;
+UPDATE t1 SET b=repeat('blob', 12345), c = 'world' where a = 1;
+# Connection default:
+set debug = '+d, innodb_cached_old_vers_offsets';
+CHECK TABLE t1;
+ERROR HY000: Lost connection to MySQL server during query
+# restart
+DROP TABLE t1;
+#
+# Repeat the scenario without the debug point.
+#
+CREATE TABLE t1 (a INT PRIMARY KEY, b TEXT, c TEXT, INDEX (b(1)));
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) NOT NULL,
+  `b` text,
+  `c` text,
+  PRIMARY KEY (`a`),
+  KEY `b` (`b`(1))
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
+# Connection con1:
+INSERT INTO t1 (a, b, c) VALUES (1, 'hello', repeat('blob ', 12345));
+BEGIN;
+UPDATE t1 SET b=repeat('blob', 12345), c = 'world' where a = 1;
+# Connection default:
+CHECK TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	check	status	OK
+# Connection con1:
+commit;
+# Connection default:
+DROP TABLE t1;

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

@@ -0,0 +1,62 @@
+--source include/have_debug.inc
+--source include/count_sessions.inc
+
+# Valgrind can hang or return spurious messages on DBUG_SUICIDE
+--source include/not_valgrind.inc
+
+--echo #
+--echo # Bug #28825617 ASSERTION FAILURE: LOB0LOB.CC.*TRX == NULLPTR
+--echo # || TRX->IS_READ_UNCOMMITTED()
+--echo #
+
+CREATE TABLE t1 (a INT PRIMARY KEY, b TEXT, c TEXT, INDEX (b(1)));
+SHOW CREATE TABLE t1;
+
+--echo # Connection con1:
+connect (con1,localhost,root,,);
+INSERT INTO t1 (a, b, c) VALUES (1, 'hello', repeat('blob ', 12345));
+BEGIN;
+UPDATE t1 SET b=repeat('blob', 12345), c = 'world' where a = 1;
+
+--echo # Connection default:
+connection default;
+set debug = '+d, innodb_cached_old_vers_offsets';
+
+--source include/expect_crash.inc
+
+--error 2013
+CHECK TABLE t1;
+
+--source include/start_mysqld.inc
+disconnect con1;
+DROP TABLE t1;
+
+--echo #
+--echo # Repeat the scenario without the debug point.
+--echo #
+
+CREATE TABLE t1 (a INT PRIMARY KEY, b TEXT, c TEXT, INDEX (b(1)));
+SHOW CREATE TABLE t1;
+
+--echo # Connection con1:
+connect (con1,localhost,root,,);
+INSERT INTO t1 (a, b, c) VALUES (1, 'hello', repeat('blob ', 12345));
+BEGIN;
+UPDATE t1 SET b=repeat('blob', 12345), c = 'world' where a = 1;
+
+--echo # Connection default:
+connection default;
+
+CHECK TABLE t1;
+
+--echo # Connection con1:
+connection con1;
+commit;
+
+--echo # Connection default:
+connection default;
+disconnect con1;
+
+DROP TABLE t1;
+
+--source include/wait_until_count_sessions.inc

storage/innobase/lob/lob0lob.cc

@@ -1303,7 +1303,6 @@ bool ref_t::check_space_id(dict_index_t *index) const {
   space_id_t ref_space_id = space_id();
 
   bool lob_ref_valid = (ref_space_id == 0 || idx_space_id == ref_space_id);
-  ut_ad(lob_ref_valid);
   return (lob_ref_valid);
 }
 #endif /* UNIV_DEBUG */
@@ -1362,7 +1361,9 @@ bool rec_check_lobref_space_id(dict_index_t *index, const rec_t *rec,
 
       byte *field_ref = data + local_len;
       ref_t ref(field_ref);
-      ut_ad(ref.check_space_id(index));
+      if (!ref.check_space_id(index)) {
+        return (false);
+      }
     }
   }
   return (true);

storage/innobase/rem/rec.cc

@@ -414,6 +414,10 @@ void rec_get_offsets_reverse(
 }
 
 #ifdef UNIV_DEBUG
+/** Check if the given two record offsets are identical.
+@param[in]  offsets1  field offsets of a record
+@param[in]  offsets2  field offsets of a record
+@return true if they are identical, false otherwise. */
 bool rec_offs_cmp(ulint *offsets1, ulint *offsets2) {
   ulint n1 = rec_offs_n_fields(offsets1);
   ulint n2 = rec_offs_n_fields(offsets2);
@@ -432,10 +436,18 @@ bool rec_offs_cmp(ulint *offsets1, ulint *offsets2) {
     if (field_offset_1 != field_offset_2) {
       return (false);
     }
+
+    if (len_1 != len_2) {
+      return (false);
+    }
   }
   return (true);
 }
 
+/** Print the record offsets.
+@param[in]    out         the output stream to which offsets are printed.
+@param[in]    offsets     the field offsets of the record.
+@return the output stream. */
 std::ostream &rec_offs_print(std::ostream &out, const ulint *offsets) {
   ulint n = rec_offs_n_fields(offsets);
 

storage/innobase/row/row0sel.cc

@@ -3328,6 +3328,14 @@ dberr_t Row_sel_get_clust_rec_for_mysql::operator()(
         old_vers = cached_old_vers;
 
         if (old_vers != nullptr) {
+          DBUG_EXECUTE_IF("innodb_cached_old_vers_offsets", {
+            rec_offs_make_valid(old_vers, clust_index, *offsets);
+            if (!lob::rec_check_lobref_space_id(clust_index, old_vers,
+                                                *offsets)) {
+              DBUG_SUICIDE();
+            }
+          });
+
           /* The offsets need not be same for the latest version of
           clust_rec and its old version old_vers.  Re-calculate the offsets
           for old_vers. */