The check for view security was lacking several points :
1. Check with the right set of permissions : for each table ref that
participates in a view there were the right credentials to use in it's
security_ctx member, but these weren't used for checking the credentials.
This makes hard enforcing the SQL SECURITY DEFINER|INVOKER property
consistently.
2. Because of the above the security checking for views was just ruled out
in explicit ways in several places.
3. The security was checked only for the columns of the tables that are
brought into the query from a view. So if there is no column reference
outside of the view definition it was not detecting the lack of access to
the tables in the view in SQL SECURITY INVOKER mode.
The fix below tries to fix the above 3 points.
- In function 'handle_grant_struct' when searching the memory structures for an
entry to modify, convert all entries here host.hostname is NULL to "" and compare that
with the host passed in argument "user_from".
- A user created with hostname "" is stored in "mysql.user" table as host="" but when loaded into
memory it'll be stored as host.hostname NULL. Specifiying "" as hostname means
that "any host" can connect. Thus is's correct to turn on allow_all_hosts
when such a user is found.
- Review and fix other places where host.hostname may be NULL.
after merge.
Concurrent read and update of privilege structures (like simultaneous
run of SHOW GRANTS and ADD USER) could result in server crash.
Ensure that proper locking of ACL structures is done.
No test case is provided because this bug can't be reproduced
deterministically.
Problem:
if a user was granted privileges on database "d1",
it also was able to act on "D1" (i.e. in upper case),
even on Unix with case sensitive file system.
Fix:
Initialize grant hash to use binary comparison
if lower_case_file_system is not set (on most unixes),
and case insensitive comparison otherwise (Windows, MacOSX).
Concurrent read and update of privilege structures (like simultaneous
run of SHOW GRANTS and ADD USER) could result in server crash.
Ensure that proper locking of ACL structures is done.
No test case is provided because this bug can't be reproduced
deterministically.
Added missing DBUG_xxx_RETURN statements
Fixed some usage of not initialized variables (as found by valgrind)
Ensure that we don't remove locked tables used as name locks from open table cache until unlock_table_names() are called.
This was fixed by having drop_locked_name() returning any table used as a name lock so that we can free it in unlock_table_names()
This will allow Tomas to continue with his work to use namelocks to syncronize things.
Note: valgrind still produces a lot of warnings about using not initialized code and shows memory loss errors when running the ndb tests
Crash happened when one selected data from one of INFORMATION_SCHEMA
tables and in order to build its contents server had to open view which
used stored function and table or view on which one had not global or
database-level privileges (e.g. had only table-level or had no
privileges at all).
The crash was caused by usage of check_grant() function, which assumes
that either number of tables to be inspected by it is limited explicitly
or table list used and thd->lex->query_tables_own_last value correspond
to each other (the latter should be either 0 or point to next_global
member of one of elements of this table list), in conditions when
above assumptions were not true. This fix just explicitly limits
number of tables to be inspected. Other negative effects which are
caused by the fact that thd->lex->query_tables_own_last might not
be set properly during processing of I_S tables are less disastrous
and will be reported and fixed separetely.
- fix for bug#16423 (Events: SHOW CREATE EVENT doesn't work)
- this Changeset commits makes CREATE/UPDATE/DELETE EVENT real DDL statements
by committing the currently open transaction before they are executed.
- this Changeset also fixes a trailing space problem since the very early days
of the internal cron
- adds sophisticated checking of whether mysql.event was tampered accidentally
or with purpose by an user.
- adds a lot of inline function documentation - documents everything left
uncodumented
- INTERVAL_XXXX to XXX in I_S.EVENTS.INTERVAL_FIELD
WL#1034 (Internal CRON)
Implement table-level TRIGGER privilege to control access to triggers.
Before this path global SUPER privilege was used for this purpose, that
was the big security problem.
In details, before this patch SUPER privilege was required:
- for the user at CREATE TRIGGER time to create a new trigger;
- for the user at DROP TRIGGER time to drop the existing trigger;
- for the definer at trigger activation time to execute the trigger (if the
definer loses SUPER privilege, all its triggers become unavailable);
This patch changes the behaviour in the following way:
- TRIGGER privilege on the subject table for trigger is required:
- for the user at CREATE TRIGGER time to create a new trigger;
- for the user at DROP TRIGGER time to drop the existing trigger;
- for the definer at trigger activation time to execute the trigger
(if the definer loses TRIGGER privilege on the subject table, all its
triggers on this table become unavailable).
- SUPER privilege is still required:
- for the user at CREATE TRIGGER time to explicitly set the trigger
definer to the user other than CURRENT_USER().
When the server works with database of the previous version (w/o TRIGGER
privilege), or if the database is being upgraded from the previous versions,
TRIGGER privilege is granted to whose users, who have CREATE privilege.
There are two main idea of this fix:
- introduce a common function for server and client to split user value
(<user name>@<host name>) into user name and host name parts;
- dump DEFINER clause in correct format in mysqldump.
