impossible view security".
We should not expose names of tables which are explicitly or implicitly (via
routine or trigger) used by view even if we find that they are missing.
So during building of list of prelocked tables for statement we track which
routines (and therefore tables for these routines) are used from views. We
mark elements of LEX::routines set which correspond to routines used in views
by setting Sroutine_hash_entry::belong_to_view member to point to TABLE_LIST
object for topmost view which uses routine. We propagate this mark to all
routines which are used by this routine and which we add to this set. We also
mark tables used by such routine which we add to the list of tables for
prelocking as belonging to this view.
Added error checking for errors when attempting to use stored procedures
after the mysql.proc table has been dropped, corrupted, or tampered with.
Test cases were put in a separate file (sp-destruct.test).
This bug occurs when some trigger for table used by DML statement is created
or changed while statement was waiting in lock_tables(). In this situation
prelocking set which we have calculated becames invalid which can easily lead
to errors and even in some cases to crashes.
With proposed patch we no longer silently reopen tables in lock_tables(),
instead caller of lock_tables() becomes responsible for reopening tables and
recalculation of prelocking set.
result set".
To enable full access to contents of I_S tables from stored functions
or statements that use them, we manipulate with thread's open tables
state and ensure that we won't cause deadlock when we open tables by
ignoring flushes and name-locks.
Building of contents of I_S.TABLES no longer requires locking of tables
since we use use handler::info() method with HA_STATUS_AUTO flag instead
of handler::update_auto_increment() for obtaining information about
auto-increment values. But this also means that handlers have to implement
support for HA_STATUS_AUTO flag (particularly InnoDB needs it).
* Don't activate prelocking mode for evaluating procedure arguments when it is not necessary.
* Code structure simplification and cleanup.
* Cleanup in .test files
its body, but lets each statement to get/release its own locks. This allows a broader set
of statements to be executed inside PROCEDUREs (but breaks replication)
This patch should fix BUG#8072, BUG#8766, BUG#9563, BUG#11126
of stored routines definitions even if we already have some tables open and
locked. To avoid deadlocks in this case we have to put certain restrictions
on locking of mysql.proc table.
This allows to use stored routines safely under LOCK TABLES without explicitly
mentioning mysql.proc in the list of locked tables. It also fixes bug #11554
"Server crashes on statement indirectly using non-cached function".
crash if referencing a table" and several other related bugs.
Fix for bug #11834 "Re-execution of prepared statement with dropped function
crashes server." which was spotted during work on previous bugs.
Also couple of nice cleanups:
- Replaced two separate hashes for stored routines used by statement with one.
- Now instead of doing one pass through all routines used in statement for
caching them and then doing another pass for adding their tables to table
list, we do only one pass during which do both things.
during creation.
Although it returns an error, consistent with the behaviour for other objects.
(Unclear why we would allow the creation of SPs with truncated names.)
and some SP-related cleanups.
- We don't have separate stage for calculation of list of tables
to be prelocked and doing implicit LOCK/UNLOCK any more.
Instead we calculate this list at open_tables() and do implicit
LOCK in lock_tables() (and UNLOCK in close_thread_tables()).
Also now we support cases when same table (with same alias) is
used several times in the same query in SP.
- Cleaned up execution of SP. Moved all common code which handles
LEX and does preparations before statement execution or complex
expression evaluation to auxilary sp_lex_keeper class. Now
all statements in SP (and corresponding instructions) that
evaluate expression which can contain subquery have their
own LEX.
Collect all tables and SPs refered by a statement, and open all tables
with an implicit LOCK TABLES. Do find things refered by triggers and views,
we open them first (and then repeat this until nothing new is found), before
doing the actual lock tables.
Phase 2: Make SPs belong to a DB, and use qualified names.
As a side effect, using USE in an SP is no longer allowed.
(It just doesn't work otherwise.)
make characteristics (and SHOW) work right, we had to separate the old
definition blob in the mysql.proc table into separate fields for parameters,
return type, and body, and handle the characteristics (like SQL SECURITY)
separately... and then reassemble the CREATE string for parsing, of course.
This is rather ugly, mostly the parser bit. (Hopefully that will be better
with the new parser.)
Expanded the mysql.proc table, reworked the find/create/drop functions
completely, added new functions for FUNCTIONs (lotta functions here :),
got rid of some unnecessary use of Item_strings while at it. Extended
the parser correspondingly, and fiddled around a bit to make SP FUNCTIONs
coexist with UDFs.
Can now CREATE and DROP FUNCTIONs. Invoking yet to come...
Fixed backpatching of forward jumps.
Implemented LOOP, WHILE, REPEAT (temporarily known as SPREPEAT).
Known bug: Expression evaluation still not quite ok (e.g. "x > 0"),
which is why IF and CASE is not yet implemented.
