BUG#30752 rpl_dual_pos_advance valgrind (jump depends on uninitialized LOG_INFO)
Problem: one thread could read uninitialized memory from (the stack of) another thread. Fix: swapped order of initializing the memory and making it available to the other thread. Fix: put lock around the statement that makes the memory available to the other thread. Fix: all fields of the struct are now initialized in the constructor, to avoid future problems. sql/sql_class.h: Initialize all members in constructor for more safe future code. sql/sql_repl.cc: Swap order so that linfo is first initialized, then assigned, instead of the other way around. Put a lock around the assignment. We use LOCK_thread_count since log_in_use uses it: log_in_use may be running concurrently, called from MYSQL_LOG::purge_logs.
This commit is contained in:
parent
eefbdfdb03
commit
42cea00e03
@ -159,7 +159,13 @@ typedef struct st_log_info
|
||||
my_off_t pos;
|
||||
bool fatal; // if the purge happens to give us a negative offset
|
||||
pthread_mutex_t lock;
|
||||
st_log_info():fatal(0) { pthread_mutex_init(&lock, MY_MUTEX_INIT_FAST);}
|
||||
st_log_info()
|
||||
: index_file_offset(0), index_file_start_offset(0),
|
||||
pos(0), fatal(0)
|
||||
{
|
||||
log_file_name[0] = '\0';
|
||||
pthread_mutex_init(&lock, MY_MUTEX_INIT_FAST);
|
||||
}
|
||||
~st_log_info() { pthread_mutex_destroy(&lock);}
|
||||
} LOG_INFO;
|
||||
|
||||
|
@ -364,7 +364,6 @@ void mysql_binlog_send(THD* thd, char* log_ident, my_off_t pos,
|
||||
name=0; // Find first log
|
||||
|
||||
linfo.index_file_offset = 0;
|
||||
thd->current_linfo = &linfo;
|
||||
|
||||
if (mysql_bin_log.find_log_pos(&linfo, name, 1))
|
||||
{
|
||||
@ -373,6 +372,10 @@ void mysql_binlog_send(THD* thd, char* log_ident, my_off_t pos,
|
||||
goto err;
|
||||
}
|
||||
|
||||
pthread_mutex_lock(&LOCK_thread_count);
|
||||
thd->current_linfo = &linfo;
|
||||
pthread_mutex_unlock(&LOCK_thread_count);
|
||||
|
||||
if ((file=open_binlog(&log, log_file_name, &errmsg)) < 0)
|
||||
{
|
||||
my_errno= ER_MASTER_FATAL_ERROR_READING_BINLOG;
|
||||
@ -1338,7 +1341,6 @@ bool mysql_show_binlog_events(THD* thd)
|
||||
name=0; // Find first log
|
||||
|
||||
linfo.index_file_offset = 0;
|
||||
thd->current_linfo = &linfo;
|
||||
|
||||
if (mysql_bin_log.find_log_pos(&linfo, name, 1))
|
||||
{
|
||||
@ -1346,6 +1348,10 @@ bool mysql_show_binlog_events(THD* thd)
|
||||
goto err;
|
||||
}
|
||||
|
||||
pthread_mutex_lock(&LOCK_thread_count);
|
||||
thd->current_linfo = &linfo;
|
||||
pthread_mutex_unlock(&LOCK_thread_count);
|
||||
|
||||
if ((file=open_binlog(&log, linfo.log_file_name, &errmsg)) < 0)
|
||||
goto err;
|
||||
|
||||
|
Loading…
x
Reference in New Issue
Block a user