When importing a dump file from MariaDB to MySQL the following error appears and forces MySQL service to restart:
ERROR 2013 (HY000) at line 2286533: Lost connection to MySQL server during query
error in MySQL error log file:
2022-02-02T12:07:43.397210Z 0 [ERROR] [MY-013183] [InnoDB] Assertion failure: ddl0buffer.cc:204:ptr < bounds.second thread 139877533333248 InnoDB: We intentionally generate a memory trap. InnoDB: Submit a detailed bug report to http://bugs.mysql.com. InnoDB: If you get repeated assertion failures or crashes, even InnoDB: immediately after the mysqld startup, there may be InnoDB: corruption in the InnoDB tablespace. Please refer to InnoDB: http://dev.mysql.com/doc/refman/8.0/en/forcing-innodb-recovery.html InnoDB: about forcing recovery. 12:07:43 UTC - mysqld got signal 6 ; Most likely, you have hit a bug, but this error can also be caused by malfunctioning hardware. Thread pointer: 0x0 Attempting backtrace. You can use the following information to find out where mysqld died. If you see no messages after this, something went terribly wrong... stack_bottom = 0 thread_stack 0x100000 /usr/sbin/mysqld(my_print_stacktrace(unsigned char const*, unsigned long)+0x3d) [0x1f8622d] /usr/sbin/mysqld(handle_fatal_signal+0x32b) [0xfecfbb] /lib64/libpthread.so.0(+0xf630) [0x7f389d0a1630] /lib64/libc.so.6(gsignal+0x37) [0x7f389b357387] /lib64/libc.so.6(abort+0x148) [0x7f389b358a78] /usr/sbin/mysqld() [0xd37acb] /usr/sbin/mysqld(ddl::Key_sort_buffer::serialize(std::pair<unsigned char*, unsigned long>, std::function<dberr_t (std::pair<unsigned char*, unsigned long>, unsigned long&)>&&)+0x3b0) [0x2414410] /usr/sbin/mysqld(ddl::Builder::bulk_add_row(ddl::Cursor&, ddl::Row&, unsigned long, std::function<dberr_t ()>&&)+0x1d8) [0x241d848] /usr/sbin/mysqld(ddl::Builder::add_row(ddl::Cursor&, ddl::Row&, unsigned long, std::function<dberr_t ()>&&)+0xa5) [0x241dcd5] /usr/sbin/mysqld() [0x23730c1] /usr/sbin/mysqld(Parallel_reader::Ctx::traverse_recs(PCursor*, mtr_t*)+0x4c6) [0x2196a06] /usr/sbin/mysqld(Parallel_reader::Ctx::traverse()+0x197) [0x21988d7] /usr/sbin/mysqld(Parallel_reader::worker(Parallel_reader::Thread_ctx*)+0x2d5) [0x219e055] /usr/sbin/mysqld(std::thread::_State_impl<std::thread::_Invoker<std::tuple<Detached_thread, void (Parallel_reader::*)(Parallel_reader::Thread_ctx*), Parallel_reader*, Parallel_reader::Thread_ctx*> > >::_M_run()+0xd3) [0x2194ea3] /usr/sbin/mysqld() [0x2788dcf] /lib64/libpthread.so.0(+0x7ea5) [0x7f389d099ea5] /lib64/libc.so.6(clone+0x6d) [0x7f389b41fb0d] The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains information that should help you find out what is causing the crash.
In the .sql dump file the line where error occurs is 2286533 and contains:
ALTER TABLE 'wp_options'
This table is in InnoDB but by changing the engine to MyISAM import works.
On the official MySQL website, there is a bug report with this error that is not publically visible because the author selected the “Does this bug report represent a security vulnerability?” option when reporting the bug, meaning that It can be used as an exploit. That’s quite understandable because on a shared server single user can restart mysqld service with a simple db import causing problems to all other users.
On MariaDB import succeeded so the problem appears to affect only MySQL servers.