Attempt to create a procedure with the DEFINER clause resulted in
abnormal server termination in case the server run with the option
--skip-grant-tables=1.
The reason of abnormal termination is that on handling of the DEFINER
clause, not initialized data members of acl_cache is accessed, that led
to server crash.
Behaviour of the server for considered use case must be the same
as for embedded server. Than means, if a security subsytem wasn't
initialized (server is started with the option --skip-grant-tables=1)
return success from get_current_user() without further access to the
acl_cache that obviously not initialized.
Additionlly, AUTHID::is_role was modified to handle the case when
a host part of the user name isn't provided. Treat this case as if
the empty host name is provided.
- Needless engaged_ removed;
- SCOPE_VALUE, SCOPE_SET, SCOPE_CLEAR macros for neater declaration;
- IF_CLASS / IF_NOT_CLASS SFINAE checkers to pass arg by value or
reference;
- inline keyword;
- couple of refactorings of temporary free_list.
Example:
{
auto _= make_scope_value(var, tmp_value);
}
make_scope_value(): a function which returns RAII object which temporary
changes a value of a variable
detail::Scope_value: actual implementation of such RAII class.
It shouldn't be used directly! That's why it's inside a namespace detail.
get_all_tables() skipped tables if the user has no privileges on
the schema itself and no granted privilege on any tables in the schema.
that is, it was skipping performance_schema tables (privileges
on them aren't explicitly granted, but internally hard-coded)
To fix:
* extend ACL_internal_table_access::check() method with
`bool any_combination_will_do`
* fix all perfschema privilege checks to take it into account.
* don't reuse table_acl_check object for all tables, initialize it
for every table otherwise GRANT_INTERNAL_INFO will leak
* remove incorrect privilege check from get_all_tables()
during FLUSH PRIVILEGES, allow_all_hosts temporarily goes out of sync
with acl_check_hosts and acl_wild_hosts.
As it's tested in acl_check_host() without a mutex, let's re-test it
under a mutex to make sure the value is correct.
Note that it's just an optimization and it's ok to see outdated
allow_all_hosts value here.
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Change the type of my_hash_get_key to:
1) Return const
2) Change the context parameter to be const void*
Also fix casting in hash adjacent areas.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
The functions queue_compare, qsort2_cmp, and qsort_cmp2
all had similar interfaces, and were used interchangable
and unsafely cast to one another.
This patch consolidates the functions all into the
qsort_cmp2 interface.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
The problem was that when using clang + asan, we do not get a correct value
for the thread stack as some local variables are not allocated at the
normal stack.
It looks like that for example clang 18.1.3, when compiling with
-O2 -fsanitize=addressan it puts local variables and things allocated by
alloca() in other areas than on the stack.
The following code shows the issue
Thread 6 "mariadbd" hit Breakpoint 3, do_handle_one_connection
(connect=0x5080000027b8,
put_in_cache=<optimized out>) at sql/sql_connect.cc:1399
THD *thd;
1399 thd->thread_stack= (char*) &thd;
(gdb) p &thd
(THD **) 0x7fffedee7060
(gdb) p $sp
(void *) 0x7fffef4e7bc0
The address of thd is 24M away from the stack pointer
(gdb) info reg
...
rsp 0x7fffef4e7bc0 0x7fffef4e7bc0
...
r13 0x7fffedee7060 140737185214560
r13 is pointing to the address of the thd. Probably some kind of
"local stack" used by the sanitizer
I have verified this with gdb on a recursive call that calls alloca()
in a loop. In this case all objects was stored in a local heap,
not on the stack.
To solve this issue in a portable way, I have added two functions:
my_get_stack_pointer() returns the address of the current stack pointer.
The code is using asm instructions for intel 32/64 bit, powerpc,
arm 32/64 bit and sparc 32/64 bit.
Supported compilers are gcc, clang and MSVC.
For MSVC 64 bit we are using _AddressOfReturnAddress()
As a fallback for other compilers/arch we use the address of a local
variable.
my_get_stack_bounds() that will return the address of the base stack
and stack size using pthread_attr_getstack() or NtCurrentTed() with
fallback to using the address of a local variable and user provided
stack size.
Server changes are:
- Moving setting of thread_stack to THD::store_globals() using
my_get_stack_bounds().
- Removing setting of thd->thread_stack, except in functions that
allocates a lot on the stack before calling store_globals(). When
using estimates for stack start, we reduce stack_size with
MY_STACK_SAFE_MARGIN (8192) to take into account the stack used
before calling store_globals().
I also added a unittest, stack_allocation-t, to verify the new code.
Reviewed-by: Sergei Golubchik <serg@mariadb.org>
This commit introduces a reset of password errors counter on any alter user
command for the altered user. This is done so as to not require a
complete privilege system reload.
