diff options
author | Monty <monty@mariadb.org> | 2020-12-14 15:27:07 +0200 |
---|---|---|
committer | Monty <monty@mariadb.org> | 2021-01-15 14:12:26 +0200 |
commit | 9a60e89a907618eed1cabc63843fd983baa17fb7 (patch) | |
tree | a9c1836e89b8ff92a9817e159ab859b0658f7461 | |
parent | 76b58c2af78cb25212309f5f00554750cbdb5372 (diff) | |
download | mariadb-git-9a60e89a907618eed1cabc63843fd983baa17fb7.tar.gz |
Fixed some possible usage of freed memory
- Create_tmp_table::finalize didn't clear file after delete which
could cause a double free. This is however not a likely problem as
this code path is very unlikely to happen
- free_tmp_table() could do handler calls even if the table was never
opened. Fixed by adding a test if the table is opened.
-rw-r--r-- | sql/sql_select.cc | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 5422346884d..812917df3ad 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -18675,6 +18675,7 @@ bool Create_tmp_table::finalize(THD *thd, if (table->file->set_ha_share_ref(&share->ha_share)) { delete table->file; + table->file= 0; goto err; } table->file->set_table(table); @@ -19913,11 +19914,14 @@ free_tmp_table(THD *thd, TABLE *entry) if (entry->file && entry->is_created()) { - DBUG_ASSERT(entry->db_stat); - entry->file->ha_index_or_rnd_end(); - entry->file->info(HA_STATUS_VARIABLE); - thd->tmp_tables_size+= (entry->file->stats.data_file_length + - entry->file->stats.index_file_length); + if (entry->db_stat) + { + /* The table was properly opened in open_tmp_table() */ + entry->file->ha_index_or_rnd_end(); + entry->file->info(HA_STATUS_VARIABLE); + thd->tmp_tables_size+= (entry->file->stats.data_file_length + + entry->file->stats.index_file_length); + } entry->file->ha_drop_table(entry->s->path.str); delete entry->file; } |