revision-id: cb8d888c42aa9504db2df686f0e963b99079e287 (mariadb-5.5.63-20-gcb8d888c42a) parent(s): e5aa8ea52552759453fdd86eeab0007df1781b62 author: Sujatha Sivakumar committer: Sujatha Sivakumar timestamp: 2019-04-24 11:40:52 +0530 message: MDEV-17260: Memory leaks in mysqlbinlog Problem: ======== The mysqlbinlog tool is leaking memory, causing failures in various tests when compiling and testing with AddressSanitizer or LeakSanitizer like this: cmake -DCMAKE_BUILD_TYPE=Debug -DWITH_ASAN:BOOL=ON /path/to/source make -j$(nproc) cd mysql-test ASAN_OPTIONS=abort_on_error=1 ./mtr --parallel=auto rpl.rpl_row_mysqlbinlog CURRENT_TEST: rpl.rpl_row_mysqlbinlog Direct leak of 112 byte(s) in 1 object(s) allocated from: #0 0x4eff87 in __interceptor_malloc (/dev/shm/5.5/client/mysqlbinlog+0x4eff87) #1 0x60eaab in my_malloc /mariadb/5.5/mysys/my_malloc.c:41:10 #2 0x5300dd in Log_event::read_log_event(char const*, unsigned int, char const**, Format_description_log_event const*, char) /mariadb/5.5/sql/log_event.cc:1568: #3 0x564a9c in dump_remote_log_entries(st_print_event_info*, char const*) /mariadb/5.5/client/mysqlbinlog.cc:1978:17 Analysis: ======== 'mysqlbinlog' tool is being used to read binary log events from a remote server. While reading binary log, if a fake rotate event is found following actions are taken. If 'to-last-log' option is specified, then fake rotate event is processed. In the absence of 'to-last-log' skip the fake rotate event. In this skipped case the fake rotate event object is not getting cleaned up resulting in memory leak. Fix: === Cleanup the fake rotate event. This issues is already fixed in MariaDB 10.0.23 and higher versions as part of commit c3018b0ff4fb02c029787d03867adf0530607bab --- client/mysqlbinlog.cc | 2 ++ 1 file changed, 2 insertions(+) diff --git a/client/mysqlbinlog.cc b/client/mysqlbinlog.cc index 250dc609891..1a11e3e697b 100644 --- a/client/mysqlbinlog.cc +++ b/client/mysqlbinlog.cc @@ -2020,6 +2020,7 @@ static Exit_status dump_remote_log_entries(PRINT_EVENT_INFO *print_event_info, if ((rev->ident_len != logname_len) || memcmp(rev->new_log_ident, logname, logname_len)) { + delete ev; DBUG_RETURN(OK_CONTINUE); } /* @@ -2028,6 +2029,7 @@ static Exit_status dump_remote_log_entries(PRINT_EVENT_INFO *print_event_info, log. If we are running with to_last_remote_log, we print it, because it serves as a useful marker between binlogs then. */ + delete ev; continue; } len= 1; // fake Rotate, so don't increment old_off