Let us make innodb_buffer_pool_filename a read-only variable
so that a malicious user cannot cause an important file to be
deleted on InnoDB shutdown. An attempt to delete a directory
will fail because it is not a regular file, but what if the
variable pointed to (say) ibdata1, ib_logfile0 or some *.ibd file?
It does not seem to make much sense for this parameter to be
configurable in the first place, but we will not change that in order
to avoid breaking compatibility.
Several MYSQL_SYSVAR_STR parameters that employ both a validate
function callback fail to copy the string for saving the
validated value. The affected variables include the following:
innodb_ft_aux_table
innodb_ft_server_stopword_table
innodb_ft_user_stopword_table
innodb_buffer_pool_filename
The test case is an enhanced version of
mysql/mysql-server@0b0c30641f
and the code changes are inspired by their fixes.
We are also importing and adjusting the test innodb_fts.stopword
to get coverage for the variable innodb_ft_user_stopword_table.
buf_dump(), buf_load(): Protect srv_buf_dump_filename with
LOCK_global_system_variables.
fts_load_user_stopword(): Minor cleanup
fts_load_stopword(): Remove the parameter global_stopword_table.
innobase_fts_load_stopword(): Protect innodb_server_stopword_table
against concurrent SET GLOBAL.
