While performing SAST scanning using Cppcheck against source code of
commit 81196469, several code vulnerabilities were found.
Fix following issues:
1. Parameters of `snprintf` function are incorrect.
Cppcheck error:
client/mysql_plugin.c:1228: error: snprintf format string requires 6 parameters but only 5 are given.
It is due to commit 630d7229 introduced option `--lc-messages-dir`
in the bootstrap command. However the parameter was not even given
in the `snprintf` after changing the format string.
Fix:
Restructure the code logic and correct the function parameters for
`snprintf`.
2. Null pointer is used in a `snprintf` which could cause a crash.
Cppcheck error:
extra/mariabackup/xbcloud.cc:2534: error: Null pointer dereference
The code intended to print the swift_project name, if the
opt_swift_project_id is NULL but opt_swift_project is not NULL.
However the parameter of `snprintf` was mistakenly using
`opt_swift_project_id`.
Fix:
Change to use the correct string from `opt_swift_project`.
3. Potential double release of a memory
Cppcheck error:
plugin/auth_pam/testing/pam_mariadb_mtr.c:69: error: Memory pointed to by 'resp' is freed twice.
A pointer `resp` is reused and allocated new memory after it has been
freed. However, `resp` was not set to NULL after freed.
Potential double release of the same pointer if the call back
function doesn't allocate new memory for `resp` pointer.
Fix:
Set the `resp` pointer to NULL after the first free() to make sure
the same address is not freed twice.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services, Inc.
The MariaDB code base uses strcat() and strcpy() in several
places. These are known to have memory safety issues and their usage is
discouraged. Common security scanners like Flawfinder flags them. In MariaDB we
should start using modern and safer variants on these functions.
This is similar to memory issues fixes in 19af1890b5
and 9de9f105b5 but now replace use of strcat()
and strcpy() with safer options strncat() and strncpy().
However, add '\0' forcefully to make sure the result string is correct since
for these two functions it is not guaranteed what new string will be null-terminated.
Example:
size_t dest_len = sizeof(g->Message);
strncpy(g->Message, "Null json tree", dest_len); strncat(g->Message, ":",
sizeof(g->Message) - strlen(g->Message)); size_t wrote_sz = strlen(g->Message);
size_t cur_len = wrote_sz >= dest_len ? dest_len - 1 : wrote_sz;
g->Message[cur_len] = '\0';
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the BSD-new
license. I am contributing on behalf of my employer Amazon Web Services
-- Reviewer and co-author Vicențiu Ciorbaru <vicentiu@mariadb.org>
-- Reviewer additions:
* The initial function implementation was flawed. Replaced with a simpler
and also correct version.
* Simplified code by making use of snprintf instead of chaining strcat.
* Simplified code by removing dynamic string construction in the first
place and using static strings if possible. See connect storage engine
changes.
In commit 28325b0863
a compile-time option was introduced to disable the macros
DBUG_ENTER and DBUG_RETURN or DBUG_VOID_RETURN.
The parameter name WITH_DBUG_TRACE would hint that it also
covers DBUG_PRINT statements. Let us do that: WITH_DBUG_TRACE=OFF
shall disable DBUG_PRINT() as well.
A few InnoDB recovery tests used to check that some output from
DBUG_PRINT("ib_log", ...) is present. We can live without those checks.
Reviewed by: Vladislav Vaintroub
Let us use the normal platform-specific preprocessor symbols
__linux__, __sun__, _AIX instead of some homebrew ones.
The preprocessor symbol UNIV_HPUX must have lost its meaning
by f6deb00a56 (note: the symbol
UNIV_HPUX10 is being checked for, but only UNIV_HPUX is defined).
xb_read_delta_metadata(): For ROW_FORMAT=COMPRESSED tables, initialize
the info.zip_size with the physical page size and let info.page_size
remain the logical page size, like xb_delta_open_matching_space()
expects it to be ever since
commit 0a1c3477bf (MDEV-18493).
Even though commit b817afaa1c passed
the test mariabackup.compress_qpress, that test turned out to be
too small to reveal one more problem that had previously been prevented
by the existence of ctrl_mutex. I did not realize that there can be
multiple concurrent callers to compress_write(). One of them is the
log copying thread; further callers are data file copying threads
(default: --parallel=1).
By default, there is only one compression worker thread
(--compress-threads=1).
compress_write(): Fix a race condition between threads that would
use the same worker thread object. Make thd->data_avail contain the
thread identifier of the submitter, and add thd->avail_cond to
notify other compress_write() threads that are waiting for a slot.
This reverts the revert 4f62dfe676
and fixes the hang that was introduced when ctrl_mutex was removed.
The test mariabackup.compress_qpress covers this code, but the
test is skipped if a stand-alone qpress executable is not available.
It is not available in many software repositories, possibly because
the code base has not been updated since 2010.
This was tested with an executable that was compile from the source
code at http://www.quicklz.com/qpress-11-source.zip (after adding
a missing #include <unistd.h> for the definition of isatty()).
Compared to the grandparent commit (before the revert), the changes
are as follows:
comp_thread_ctxt_t::done_cond: A separate condition for completed
compression, signaling that thd->to_len has been updated.
compress_write(): Replace some threads[i] with thd.
Reset thd->to_len = 0 after consuming the compressed data.
compress_worker_thread_func(): After consuming the uncompressed
data, set thd->data_avail = FALSE. After compressing, signal
thd->done_cond.
comp_thread_ctxt_t: Remove ctrl_mutex, ctrl_cond, started. We do not
actually need them for anything.
destroy_worker_thread(): Split from destroy_worker_threads().
create_worker_threads(): We already initialize
thd->data_avail=FALSE and thd->cancelled=FALSE before
invoking pthread_create(). If any thread creation fails,
clean up by destroy_worker_thread().
compress_worker_thread_func(): Assume that thd->started and
thd->data_avail are already initialized.
Reviewed by: Vladislav Vaintroub
When "mariabackup --target-dir=$basedir --incremental-dir=$incremental_dir"
is running and is moving a new table file (e.g. `db1/t1.new`) from the
incremental directory to the base directory, it needs to verify that the base
backup database directory (e.g. `$basedir/db1`) really exists
(or create it otherwise).
The table `db1/t1` can come from a new database `db1` which
was created during the base mariabackup execution time.
In such case the directory `db1` exists only in the incremental directory,
but does not exist in the base directory.
don't initialize error_log_handler_list in set_handlers()
* error_log_handler_list is initialized to LOG_FILE early, in init_base()
* set_handlers always reinitializes it to LOG_FILE, so it's pointless
* after init_base() concurrent threads start using sql_log_warning,
so following set_handlers() shouldn't modify error_log_handler_list
without some protection
We will remove the parameter innodb_disallow_writes because it is badly
designed and implemented. The parameter was never allowed at startup.
It was only internally used by Galera snapshot transfer.
If a user executed
SET GLOBAL innodb_disallow_writes=ON;
the server could hang even on subsequent read operations.
During Galera snapshot transfer, we will block writes
to implement an rsync friendly snapshot, as follows:
sst_flush_tables() will acquire a global lock by executing
FLUSH TABLES WITH READ LOCK, which will block any writes
at the high level.
sst_disable_innodb_writes(), invoked via ha_disable_internal_writes(true),
will suspend or disable InnoDB background tasks or threads that could
initiate writes. As part of this, log_make_checkpoint() will be invoked
to ensure that anything in the InnoDB buf_pool.flush_list will be written
to the data files. This has the nice side effect that the Galera joiner
will avoid crash recovery.
The changes to sql/wsrep.cc and to the tests are based on a prototype
that was developed by Jan Lindström.
Reviewed by: Jan Lindström
This commit adds correct handling of binlogs for SST using rsync
or mariabackup. Before this fix, binlogs were handled incorrectly -
- only one (last) binary log file was transferred during SST, which
then led to various failures (for example, when trying to list all
events from the binary log). These bugs were long masked by flaws
in the primitive binlogs handling code in the SST scripts, which
causing binary logs files to be erased after transfer or not added
to the binlog index on the joiner node. Now the correct transfer
of all binary logs (not just the last of the binary log files) has
been implemented both for the rsync (at the script level) and for
the mariabackup (at the level of the main utility code).
This commit also adds a new sst_max_binlogs=<n> parameter, which
can be located in the [sst] section or in the [xtrabackup] section
(historically, supported for mariabackup only, not for rsync), or
in one of the server sections. This parameter specifies the number
of binary log files to be sent to the joiner node during SST. This
option is added for compatibility with old SST scripting behavior,
which can be emulated by setting the sst_max_binlogs=1 (although
in general this can cause problems for the reasons described above).
In addition, setting the sst_max_binlogs=0 can be used to suppress
the transmission of binary logs to the joiner nodes during SST
(although sometimes a single file with the current binary log can
still be transmitted to the joiner, even with sst_max_binlogs=0,
because this sometimes necessary in modes that involve the use of
GTIDs with Galera).
Also, this commit ensures correct handling of paths to various
innodb files and directories in the SST scripts, and fixes some
problems with this that existed in mariabackup utility (which
were associated with incorrect handling of the innodb_data_dir
parameter in some scenarios).
In addition, this commit contains the following enhancements:
1) Added tests for mtr, which check the correct work with binlogs
after SST (using rsync and mariabackup);
2) Added correct handling of slashes at the end of all paths that
the SST script receives as parameters;
3) Improved parsing code for --mysqld-args parameters. Now it
correctly processes the sequence "--" after the name of the
one-letter option;
4) Checking the secret signature during joiner authentication
is made independent of presence of bash (as a unix shell)
in the system and diff utility no longer needed to check
certificates compliance;
5) All directories that are necessary for the correct placement
of various logs are automatically created by SST scripts in
advance (before running mariabackup on the joiner node);
6) Removal of old binary logs on joiner is done using the binlog
index (if it exists) (not only by fixed pattern that based
on the current binlog name, as before);
7) Paths for placing binary logs are correctly processed if they
are set as relative paths (to the datadir);
8) SST scripts are made even more resistant to spaces in filenames
(now for binlogs);
9) In case of failure, SST scripts now always end with an exit
code other than zero;
10) SST script for rsync now correctly create a tar file with
the binlogs, even if the paths to them (in the binlog index
file) are specified as a mix of absolute and relative paths,
and even if they do not match with the datadir path specified
in the current configuration settings.
The previous threads locked need to be released too.
This occurs if the initialization of any of the non-first
mutex/conditition variables errors occurs.
