MDEV-16376 ASAN: heap-use-after-free in gcol.innodb_virtual_debug

After a failed ADD INDEX, dict_index_remove_from_cache_low()
could iterate the index fields and dereference a freed virtual
column object when trying to remove the index from the v_indexes
of the virtual column.

This regression was caused by a merge of
MDEV-16119 InnoDB lock->index refers to a freed object.

ha_innobase_inplace_ctx::clear_added_indexes(): Detach the
indexes of uncommitted indexes from virtual columns, so that
the iteration in dict_index_remove_from_cache_low() can be avoided.

ha_innobase::prepare_inplace_alter_table(): Ignore uncommitted
corrupted indexes when rejecting ALTER TABLE. (This minor bug was
revealed by the extension of the test case.)

dict_index_t::detach_columns(): Detach an index from virtual columns.
Invoked by both dict_index_remove_from_cache_low() and
ha_innobase_inplace_ctx::clear_added_indexes().

dict_col_t::detach(const dict_index_t& index): Detach an index from
a column.

dict_col_t::is_virtual(): Replaces dict_col_is_virtual().

dict_index_t::has_virtual(): Replaces dict_index_has_virtual().

1 files changed, 5 insertions, 14 deletions

diff --git a/storage/innobase/include/dict0dict.h b/storage/innobase/include/dict0dict.h
index 51ce248b98d..9822b57d190 100644
--- a/storage/innobase/include/dict0dict.h
+++ b/storage/innobase/include/dict0dict.h
@@ -750,13 +750,9 @@ dict_index_is_spatial(
 /*==================*/
 	const dict_index_t*	index)	/*!< in: index */
 	MY_ATTRIBUTE((warn_unused_result));
-/** Check whether the index contains a virtual column.
-@param[in]	index	index
-@return	nonzero for index on virtual column, zero for other indexes */
-UNIV_INLINE
-ulint
-dict_index_has_virtual(
-	const dict_index_t*	index);
+
+#define dict_index_has_virtual(index) (index)->has_virtual()
+
 /********************************************************************//**
 Check whether the index is the insert buffer tree.
 @return nonzero for insert buffer, zero for other indexes */
@@ -1964,13 +1960,8 @@ dict_index_node_ptr_max_size(
 /*=========================*/
 	const dict_index_t*	index)	/*!< in: index */
 	MY_ATTRIBUTE((warn_unused_result));
-/** Check if a column is a virtual column
-@param[in]	col	column
-@return true if it is a virtual column, false otherwise */
-UNIV_INLINE
-bool
-dict_col_is_virtual(
-	const dict_col_t*	col);
+
+#define dict_col_is_virtual(col) (col)->is_virtual()
 
 /** encode number of columns and number of virtual columns in one
 4 bytes value. We could do this because the number of columns in