Description:
"SHOW BINLOG EVENTS FROM" may lead to server crash if the FROM-position is incorrect under some circumstances.
The problem apppears on Linux SuSE 10.2 in 5.1. I'm not sure it does not exist in 5.0 and/or other platforms.
How to repeat:
1. Open mysql-test/t/ctype_cp932_binlog_stm.test
2. Line 25:
SHOW BINLOG EVENTS FROM 410|
Change to:
SHOW BINLOG EVENTS FROM 419|
(Change FROM-position from 410 to 419)
3. Run the test case:
---------------------------------------------------------------------
(ibm)[~/Documents/MySQL/devel/5.1-rt-cs-2-base/mysql-test]> run_tests ctype_cp932_binlog_stm
Logging: ./mysql-test-run.pl --tmpdir=/dev/shm/t1/tmp --vardir=/dev/shm/t1/var ctype_cp932_binlog_stm
MySQL Version 5.1.18
Using binlog format 'mixed'
Using ndbcluster when necessary, mysqld supports it
Setting mysqld to support SSL connections
Binaries are debug compiled
Using MTR_BUILD_THREAD = 0
Using MASTER_MYPORT = 9306
Using MASTER_MYPORT1 = 9307
Using SLAVE_MYPORT = 9308
Using SLAVE_MYPORT1 = 9309
Using SLAVE_MYPORT2 = 9310
Using NDBCLUSTER_PORT = 9310
Using NDBCLUSTER_PORT_SLAVE = 9311
Using IM_PORT = 9312
Using IM_MYSQLD1_PORT = 9313
Using IM_MYSQLD2_PORT = 9314
Killing Possible Leftover Processes
Removing Stale Files
Creating Directories
Installing Master Database
Installing Master Database
=======================================================
Starting Tests in the 'main' suite
TEST RESULT TIME (ms)
-------------------------------------------------------
ctype_cp932_binlog_stm [ fail ]
Errors are (from /dev/shm/t1/var/log/mysqltest-time) :
mysqltest: At line 25: query 'SHOW BINLOG EVENTS FROM 419' failed: 2013: Lost connection to MySQL server during query
(the last lines may be the most important ones)
Result from queries before failure can be found in /dev/shm/t1/var/log/ctype_cp932_binlog_stm.log
Aborting: ctype_cp932_binlog_stm failed in default mode. To continue, re-run with '--force'.
Stopping All Servers
---------------------------------------------------------------------
I failed to reproduce the problem w/o test environment -- the server returns error "ERROR 1220 (HY000): Error when executing command SHOW BINLOG EVENTS: Wrong offset or I/O error". So, it seems, some specific server settings are needed to get the problem.
Coredump:
(gdb) bt
#0 0xb7f47410 in ?? ()
#1 0xb7c3d908 in ?? ()
#2 0x00000006 in ?? ()
#3 0x0842d7cf in write_core (sig=6) at stacktrace.c:229
#4 0x082773fc in handle_segfault (sig=6) at mysqld.cc:2280
#5 0xb7f47420 in ?? ()
#6 0x00000006 in ?? ()
#7 0xb7d80801 in abort () from /lib/libc.so.6
#8 0xb7d787bb in __assert_fail () from /lib/libc.so.6
#9 0x083544b5 in Log_event::read_log_event (buf=0x89be8b8 "", event_len=256, error=0xb7c3decc, description_event=0x89be7e8) at log_event.cc:922
#10 0x08356895 in Log_event::read_log_event (file=0xb7c3e3d4, log_lock=0x0, description_event=0x89be7e8) at log_event.cc:874
#11 0x08419402 in mysql_show_binlog_events (thd=0x89bbbb8) at sql_repl.cc:1402
#12 0x082855a3 in mysql_execute_command (thd=0x89bbbb8) at sql_parse.cc:1950
#13 0x0828dca0 in mysql_parse (thd=0x89bbbb8, inBuf=0x8a07228 "SHOW BINLOG EVENTS FROM 419", length=27, found_semicolon=0xb7c3f280) at sql_parse.cc:5338
#14 0x0828e7d4 in dispatch_command (command=COM_QUERY, thd=0x89bbbb8, packet=0x89ff1c9 "", packet_length=28) at sql_parse.cc:906
#15 0x0828f97f in do_command (thd=0x89bbbb8) at sql_parse.cc:667
#16 0x0827d692 in handle_one_connection (arg=0x89bbbb8) at sql_connect.cc:1090
#17 0xb7ef9112 in start_thread () from /lib/libpthread.so.0
#18 0xb7e152ee in clone () from /lib/libc.so.6
(gdb) f 9
#9 0x083544b5 in Log_event::read_log_event (buf=0x89be8b8 "", event_len=256, error=0xb7c3decc, description_event=0x89be7e8) at log_event.cc:922
922 DBUG_ASSERT(buf[EVENT_TYPE_OFFSET] < ENUM_END_EVENT);
Description: "SHOW BINLOG EVENTS FROM" may lead to server crash if the FROM-position is incorrect under some circumstances. The problem apppears on Linux SuSE 10.2 in 5.1. I'm not sure it does not exist in 5.0 and/or other platforms. How to repeat: 1. Open mysql-test/t/ctype_cp932_binlog_stm.test 2. Line 25: SHOW BINLOG EVENTS FROM 410| Change to: SHOW BINLOG EVENTS FROM 419| (Change FROM-position from 410 to 419) 3. Run the test case: --------------------------------------------------------------------- (ibm)[~/Documents/MySQL/devel/5.1-rt-cs-2-base/mysql-test]> run_tests ctype_cp932_binlog_stm Logging: ./mysql-test-run.pl --tmpdir=/dev/shm/t1/tmp --vardir=/dev/shm/t1/var ctype_cp932_binlog_stm MySQL Version 5.1.18 Using binlog format 'mixed' Using ndbcluster when necessary, mysqld supports it Setting mysqld to support SSL connections Binaries are debug compiled Using MTR_BUILD_THREAD = 0 Using MASTER_MYPORT = 9306 Using MASTER_MYPORT1 = 9307 Using SLAVE_MYPORT = 9308 Using SLAVE_MYPORT1 = 9309 Using SLAVE_MYPORT2 = 9310 Using NDBCLUSTER_PORT = 9310 Using NDBCLUSTER_PORT_SLAVE = 9311 Using IM_PORT = 9312 Using IM_MYSQLD1_PORT = 9313 Using IM_MYSQLD2_PORT = 9314 Killing Possible Leftover Processes Removing Stale Files Creating Directories Installing Master Database Installing Master Database ======================================================= Starting Tests in the 'main' suite TEST RESULT TIME (ms) ------------------------------------------------------- ctype_cp932_binlog_stm [ fail ] Errors are (from /dev/shm/t1/var/log/mysqltest-time) : mysqltest: At line 25: query 'SHOW BINLOG EVENTS FROM 419' failed: 2013: Lost connection to MySQL server during query (the last lines may be the most important ones) Result from queries before failure can be found in /dev/shm/t1/var/log/ctype_cp932_binlog_stm.log Aborting: ctype_cp932_binlog_stm failed in default mode. To continue, re-run with '--force'. Stopping All Servers --------------------------------------------------------------------- I failed to reproduce the problem w/o test environment -- the server returns error "ERROR 1220 (HY000): Error when executing command SHOW BINLOG EVENTS: Wrong offset or I/O error". So, it seems, some specific server settings are needed to get the problem. Coredump: (gdb) bt #0 0xb7f47410 in ?? () #1 0xb7c3d908 in ?? () #2 0x00000006 in ?? () #3 0x0842d7cf in write_core (sig=6) at stacktrace.c:229 #4 0x082773fc in handle_segfault (sig=6) at mysqld.cc:2280 #5 0xb7f47420 in ?? () #6 0x00000006 in ?? () #7 0xb7d80801 in abort () from /lib/libc.so.6 #8 0xb7d787bb in __assert_fail () from /lib/libc.so.6 #9 0x083544b5 in Log_event::read_log_event (buf=0x89be8b8 "", event_len=256, error=0xb7c3decc, description_event=0x89be7e8) at log_event.cc:922 #10 0x08356895 in Log_event::read_log_event (file=0xb7c3e3d4, log_lock=0x0, description_event=0x89be7e8) at log_event.cc:874 #11 0x08419402 in mysql_show_binlog_events (thd=0x89bbbb8) at sql_repl.cc:1402 #12 0x082855a3 in mysql_execute_command (thd=0x89bbbb8) at sql_parse.cc:1950 #13 0x0828dca0 in mysql_parse (thd=0x89bbbb8, inBuf=0x8a07228 "SHOW BINLOG EVENTS FROM 419", length=27, found_semicolon=0xb7c3f280) at sql_parse.cc:5338 #14 0x0828e7d4 in dispatch_command (command=COM_QUERY, thd=0x89bbbb8, packet=0x89ff1c9 "", packet_length=28) at sql_parse.cc:906 #15 0x0828f97f in do_command (thd=0x89bbbb8) at sql_parse.cc:667 #16 0x0827d692 in handle_one_connection (arg=0x89bbbb8) at sql_connect.cc:1090 #17 0xb7ef9112 in start_thread () from /lib/libpthread.so.0 #18 0xb7e152ee in clone () from /lib/libc.so.6 (gdb) f 9 #9 0x083544b5 in Log_event::read_log_event (buf=0x89be8b8 "", event_len=256, error=0xb7c3decc, description_event=0x89be7e8) at log_event.cc:922 922 DBUG_ASSERT(buf[EVENT_TYPE_OFFSET] < ENUM_END_EVENT);