Bug #46858 Not using "thr_lock_data_init" in the plugin let the serve crash.

Description:
the following trace back shows what happens if the pugin doesn't use the function  "thr_lock_data_init". The server shouldn't get corrupted in that case, because for a plugin developer it is not obvious that the plugin init is not complete.
the trace back:

Program terminated with signal 11, Segmentation fault.
#0  0xffffe410 in __kernel_vsyscall ()
#0  0xffffe410 in __kernel_vsyscall ()
#1  0xb7f71397 in pthread_kill () from /lib/libpthread.so.0
#2  0x0852f4ab in my_write_core (sig=11) at stacktrace.c:309
#3  0x081fb0ac in handle_segfault (sig=141119476) at mysqld.cc:2718
#4  <signal handler called>
#5  0x08533873 in safe_mutex_lock (mp=0xc, my_flags=0, file=0x867f832 "thr_lock.c", line=555)
    at thr_mutex.c:170
#6  0x08531f44 in thr_lock (data=0x895799c, owner=0x89b5368, lock_type=TL_WRITE_CONCURRENT_INSERT)
    at thr_lock.c:555
#7  0x085323a1 in thr_multi_lock (data=0x88f1d6c, count=1, owner=0x89b5368) at thr_lock.c:1020
#8  0x081f3c5f in mysql_lock_tables (thd=0x89b4b40, tables=0x89140e0, count=1,
    flags=<value optimized out>, need_reopen=0xb73ae7bb) at lock.cc:321
#9  0x0824f854 in lock_tables (thd=0x89b4b40, tables=0x8913bb0, count=1, flags=0,
    need_reopen=0xb73ae7bb) at sql_base.cc:4541
#10 0x0825a877 in open_and_lock_tables_derived (thd=0x89b4b40, tables=0x8913bb0,
    derived=<value optimized out>, flags=0) at sql_base.cc:4235
#11 0x0829c5b5 in mysql_insert (thd=0x89b4b40, table_list=0x8913bb0, fields=@0x89b6020,
    values_list=@0x89b6044, update_fields=@0x89b6038, update_values=@0x89b602c, duplic=DUP_ERROR,
    ignore=false) at mysql_priv.h:1519
#12 0x0820eb64 in mysql_execute_command (thd=0x89b4b40) at sql_parse.cc:3220
#13 0x08212c39 in mysql_parse (thd=0x89b4b40,
    inBuf=0x89138d8 "INSERT INTO t1 VALUES (\"qwertz\",1)", length=34, found_semicolon=0xb73aff00)
    at sql_parse.cc:5942
#14 0x0821444f in dispatch_command (command=COM_QUERY, thd=0x89b4b40,
    packet=0x88ec439 "INSERT INTO t1 VALUES (\"qwertz\",1)", packet_length=34) at sql_parse.cc:1061
#15 0x08214ce8 in do_command (thd=0x89b4b40) at sql_parse.cc:743
#16 0x08203857 in handle_one_connection (arg=0x89b4b40) at sql_connect.cc:1158
#17 0xb7f6c192 in start_thread () from /lib/libpthread.so.0
#18 0xb7d8a02e in clone () from /lib/libc.so.6

How to repeat:
Use mysql-azalea-wl4939. Go into storage/tse and comment out line 169 in ha_tse.cc (  thr_lock_data_init(&f_lock, &lock, (void*) this);). After a make run the test tse_insert_simple.

Suggested fix:
React with an error or implement default values for the lock, which might be used if the init will not be done by the plugin. Don't forget to describe it.

see also bug#46851.

Thank you for the report.

Verified as described.

Same problem exists in 5.1

To repeat: modify CSV engine as described, then modify test tse_insert_simple as follows and run it:

$cat t/bug46858.test 
# Test of storage engine TSE as plugin.
#
# Creation:
# 2009-08-04 Hunger
#
#INSTALL PLUGIN tse SONAME 'ha_tse.so';
CREATE TABLE t1 (c1 char(20) not null, c2 int not null) ENGINE csv;
INSERT INTO t1 VALUES ("qwertz",1);
INSERT INTO t1 VALUES ("asdfgh",2);
INSERT INTO t1 VALUES ("yxcvbn",3);
INSERT INTO t1 VALUES ("QWERTZ",4);
INSERT INTO t1 VALUES ("ASDFGH",5);
INSERT INTO t1 VALUES ("YXCVBN",6);
INSERT INTO t1 VALUES ("poiuzt",7);
INSERT INTO t1 VALUES ("lkjhgf",8);
INSERT INTO t1 VALUES ("mnbvcx",9);
INSERT INTO t1 VALUES ("zbdtzhfghjuzttgfghzu",10);
#UNINSTALL PLUGIN tse ;

$cat t/bug46858-master.opt 
--log-output=FILE

is this bug present in any unmodified released version of mysql ?

Not using thr_lock_data_init, but further returning uninitialized THR_LOCK_DATA is definitely violation of thr_lock API. Suggested status: not a bug.