Bug #27326796 - MYSQL CRASH WITH INNODB ASSERTION FAILURE IN

FILE PARS0PARS.CC

Problem:
As part of bug #24938374 fix, dict_operation_lock was not taken by
fts_optimize_thread while syncing fts cache.
Due to this change, alter query is able to update SYS_TABLE rows
simultaneously. Now when fts_optimizer_thread goes open index table,
It doesn't open index table if the record corresponding to that table is
set to REC_INFO_DELETED_FLAG in SYS_TABLES and hits an assert.

Fix:
If fts sync is already in progress, Alter query would wait for sync to
complete before renaming table.

RB: #19604
Reviewed by : [email protected]

Author: sachinagarwal1111

storage/innobase/fts/fts0fts.cc

@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 2011, 2017, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2011, 2018, Oracle and/or its affiliates. All Rights Reserved.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -868,37 +868,28 @@ fts_drop_index(
 
 			err = fts_drop_index_tables(trx, index);
 
-			for(;;) {
-				bool retry = false;
-				if (index->index_fts_syncing) {
-					retry = true;
-				}
-				if (!retry){
-					fts_free(table);
-					break;
-				}
-				DICT_BG_YIELD(trx);
-			}
+			while (index->index_fts_syncing
+                                && !trx_is_interrupted(trx)) {
+                                DICT_BG_YIELD(trx);
+                        }
+
+                        fts_free(table);
+
 			return(err);
 		}
 
-		for(;;) {
-			bool retry = false;
-			if (index->index_fts_syncing) {
-				retry = true;
-			}
-			if (!retry){
-				current_doc_id = table->fts->cache->next_doc_id;
-				first_doc_id = table->fts->cache->first_doc_id;
-				fts_cache_clear(table->fts->cache);
-				fts_cache_destroy(table->fts->cache);
-				table->fts->cache = fts_cache_create(table);
-				table->fts->cache->next_doc_id = current_doc_id;
-				table->fts->cache->first_doc_id = first_doc_id;
-				break;
-			}
-			DICT_BG_YIELD(trx);
-		}
+		while (index->index_fts_syncing
+                        && !trx_is_interrupted(trx)) {
+                        DICT_BG_YIELD(trx);
+                }
+
+		current_doc_id = table->fts->cache->next_doc_id;
+		first_doc_id = table->fts->cache->first_doc_id;
+		fts_cache_clear(table->fts->cache);
+		fts_cache_destroy(table->fts->cache);
+		table->fts->cache = fts_cache_create(table);
+		table->fts->cache->next_doc_id = current_doc_id;
+		table->fts->cache->first_doc_id = first_doc_id;
 	} else {
 		fts_cache_t*            cache = table->fts->cache;
 		fts_index_cache_t*      index_cache;
@@ -908,17 +899,13 @@ fts_drop_index(
 		index_cache = fts_find_index_cache(cache, index);
 
 		if (index_cache != NULL) {
-			for(;;) {
-				bool retry = false;
-				if (index->index_fts_syncing) {
-					retry = true;
-				}
-				if (!retry && index_cache->words) {
-					fts_words_free(index_cache->words);
-					rbt_free(index_cache->words);
-					break;
-				}
-				DICT_BG_YIELD(trx);
+			while (index->index_fts_syncing
+                                && !trx_is_interrupted(trx)) {
+                                DICT_BG_YIELD(trx);
+                        }
+			if (index_cache->words) {
+				fts_words_free(index_cache->words);
+				rbt_free(index_cache->words);
 			}
 
 			ib_vector_remove(cache->indexes, *(void**) index_cache);

storage/innobase/handler/ha_innodb.cc

@@ -10364,6 +10364,7 @@ static MY_ATTRIBUTE((nonnull, warn_unused_result))
 dberr_t
 innobase_rename_table(
 /*==================*/
+	THD*            thd,    /*!< Connection thread handle */
 	trx_t*		trx,	/*!< in: transaction */
 	const char*	from,	/*!< in: old name of the table */
 	const char*	to)	/*!< in: new name of the table */
@@ -10389,6 +10390,37 @@ innobase_rename_table(
 
 	row_mysql_lock_data_dictionary(trx);
 
+	dict_table_t*   table                   = NULL;
+        table = dict_table_open_on_name(norm_from, TRUE, FALSE,
+                                        DICT_ERR_IGNORE_NONE);
+
+        /* Since DICT_BG_YIELD has sleep for 250 milliseconds,
+	Convert lock_wait_timeout unit from second to 250 milliseconds */
+        long int lock_wait_timeout = thd_lock_wait_timeout(thd) * 4;
+        if (table != NULL) {
+                for (dict_index_t* index = dict_table_get_first_index(table);
+                     index != NULL;
+                     index = dict_table_get_next_index(index)) {
+
+                        if (index->type & DICT_FTS) {
+                                /* Found */
+                                while (index->index_fts_syncing
+                                        && !trx_is_interrupted(trx)
+                                        && (lock_wait_timeout--) > 0) {
+                                        DICT_BG_YIELD(trx);
+                                }
+                        }
+                }
+                dict_table_close(table, TRUE, FALSE);
+        }
+
+        /* FTS sync is in progress. We shall timeout this operation */
+        if (lock_wait_timeout < 0) {
+                error = DB_LOCK_WAIT_TIMEOUT;
+                row_mysql_unlock_data_dictionary(trx);
+                DBUG_RETURN(error);
+        }
+
 	/* Transaction must be flagged as a locking transaction or it hasn't
 	been started yet. */
 
@@ -10498,7 +10530,7 @@ ha_innobase::rename_table(
 	++trx->will_lock;
 	trx_set_dict_operation(trx, TRX_DICT_OP_INDEX);
 
-	error = innobase_rename_table(trx, from, to);
+	error = innobase_rename_table(thd, trx, from, to);
 
 	DEBUG_SYNC(thd, "after_innobase_rename_table");
 
@@ -10544,6 +10576,12 @@ ha_innobase::rename_table(
 		error = DB_ERROR;
 	}
 
+	else if (error == DB_LOCK_WAIT_TIMEOUT) {
+                my_error(ER_LOCK_WAIT_TIMEOUT, MYF(0), to);
+
+                error = DB_LOCK_WAIT;
+        }
+
 	DBUG_RETURN(convert_error_code_to_mysql(error, 0, NULL));
 }