Add protection to not access is_open() without LOCK_log mutex

Protection added to reopen_file() and new_file_impl().

Without this we could get an assert in fn_format() as name == 0,
because the file was closed and name reset, atthe same time
new_file_impl() was called.

Author: montywi

sql/log.cc

@@ -2702,16 +2702,16 @@ int MYSQL_LOG::generate_new_name(char *new_name, const char *log_name)
 void MYSQL_QUERY_LOG::reopen_file()
 {
   char *save_name;
-
   DBUG_ENTER("MYSQL_LOG::reopen_file");
+
+  mysql_mutex_lock(&LOCK_log);
   if (!is_open())
   {
     DBUG_PRINT("info",("log is closed"));
+    mysql_mutex_unlock(&LOCK_log);
     DBUG_VOID_RETURN;
   }
 
-  mysql_mutex_lock(&LOCK_log);
-
   save_name= name;
   name= 0;				// Don't free name
   close(LOG_CLOSE_TO_BE_OPENED);
@@ -2870,13 +2870,6 @@ bool MYSQL_QUERY_LOG::write(THD *thd, time_t current_time,
   DBUG_ENTER("MYSQL_QUERY_LOG::write");
 
   mysql_mutex_lock(&LOCK_log);
-
-  if (!is_open())
-  {
-    mysql_mutex_unlock(&LOCK_log);
-    DBUG_RETURN(0);
-  }
-
   if (is_open())
   {						// Safety agains reopen
     int tmp_errno= 0;
@@ -3100,7 +3093,9 @@ void MYSQL_BIN_LOG::cleanup()
     }
 
     inited= 0;
+    mysql_mutex_lock(&LOCK_log);
     close(LOG_CLOSE_INDEX|LOG_CLOSE_STOP_EVENT);
+    mysql_mutex_unlock(&LOCK_log);
     delete description_event_for_queue;
     delete description_event_for_exec;
 
@@ -3257,10 +3252,11 @@ bool MYSQL_BIN_LOG::open(const char *log_name,
 {
   File file= -1;
   xid_count_per_binlog *new_xid_list_entry= NULL, *b;
-
   DBUG_ENTER("MYSQL_BIN_LOG::open");
   DBUG_PRINT("enter",("log_type: %d",(int) log_type_arg));
 
+  mysql_mutex_assert_owner(&LOCK_log);
+
   if (!is_relay_log)
   {
     if (!binlog_state_recover_done)
@@ -4842,21 +4838,21 @@ int MYSQL_BIN_LOG::new_file_impl(bool need_lock)
   bool delay_close= false;
   File old_file;
   LINT_INIT(old_file);
-
   DBUG_ENTER("MYSQL_BIN_LOG::new_file_impl");
+
+  if (need_lock)
+    mysql_mutex_lock(&LOCK_log);
+  mysql_mutex_assert_owner(&LOCK_log);
+
   if (!is_open())
   {
     DBUG_PRINT("info",("log is closed"));
+    mysql_mutex_unlock(&LOCK_log);
     DBUG_RETURN(error);
   }
 
-  if (need_lock)
-    mysql_mutex_lock(&LOCK_log);
   mysql_mutex_lock(&LOCK_index);
 
-  mysql_mutex_assert_owner(&LOCK_log);
-  mysql_mutex_assert_owner(&LOCK_index);
-
   /* Reuse old name if not binlog and not update log */
   new_name_ptr= name;
 
@@ -4989,9 +4985,9 @@ int MYSQL_BIN_LOG::new_file_impl(bool need_lock)
                      new_name_ptr, errno);
   }
 
+  mysql_mutex_unlock(&LOCK_index);
   if (need_lock)
     mysql_mutex_unlock(&LOCK_log);
-  mysql_mutex_unlock(&LOCK_index);
 
   DBUG_RETURN(error);
 }
@@ -7775,9 +7771,11 @@ int MYSQL_BIN_LOG::wait_for_update_bin_log(THD* thd,
 void MYSQL_BIN_LOG::close(uint exiting)
 {					// One can't set log_type here!
   bool failed_to_save_state= false;
-
   DBUG_ENTER("MYSQL_BIN_LOG::close");
   DBUG_PRINT("enter",("exiting: %d", (int) exiting));
+
+  mysql_mutex_assert_owner(&LOCK_log);
+
   if (log_state == LOG_OPENED)
   {
 #ifdef HAVE_REPLICATION

sql/mysqld.cc

@@ -4928,9 +4928,17 @@ static int init_server_components()
     unireg_abort(1);
   }
 
-  if (opt_bin_log && mysql_bin_log.open(opt_bin_logname, LOG_BIN, 0,
-                                        WRITE_CACHE, max_binlog_size, 0, TRUE))
-    unireg_abort(1);
+  if (opt_bin_log)
+  {
+    int error;
+    mysql_mutex_t *log_lock= mysql_bin_log.get_log_lock();
+    mysql_mutex_lock(log_lock);
+    error= mysql_bin_log.open(opt_bin_logname, LOG_BIN, 0,
+                              WRITE_CACHE, max_binlog_size, 0, TRUE);
+    mysql_mutex_unlock(log_lock);
+    if (error)
+      unireg_abort(1);
+  }
 
 #ifdef HAVE_REPLICATION
   if (opt_bin_log && expire_logs_days)

sql/rpl_rli.cc

@@ -208,6 +208,7 @@ a file name for --relay-log-index option", opt_relaylog_index_name);
     Master_info* mi= rli->mi;
     char buf_relay_logname[FN_REFLEN], buf_relaylog_index_name_buff[FN_REFLEN];
     char *buf_relaylog_index_name= opt_relaylog_index_name;
+    mysql_mutex_t *log_lock;
 
     create_logfile_name_with_suffix(buf_relay_logname,
                                     sizeof(buf_relay_logname),
@@ -227,14 +228,18 @@ a file name for --relay-log-index option", opt_relaylog_index_name);
       note, that if open() fails, we'll still have index file open
       but a destructor will take care of that
     */
+    log_lock= rli->relay_log.get_log_lock();
+    mysql_mutex_lock(log_lock);
     if (rli->relay_log.open_index_file(buf_relaylog_index_name, ln, TRUE) ||
         rli->relay_log.open(ln, LOG_BIN, 0, SEQ_READ_APPEND,
                             mi->rli.max_relay_log_size, 1, TRUE))
     {
+      mysql_mutex_unlock(log_lock);
       mysql_mutex_unlock(&rli->data_lock);
       sql_print_error("Failed when trying to open logs for '%s' in init_relay_log_info(). Error: %M", ln, my_errno);
       DBUG_RETURN(1);
     }
+    mysql_mutex_unlock(log_lock);
   }
 
   /* if file does not exist */

sql/slave.cc

@@ -5990,6 +5990,7 @@ static int queue_event(Master_info* mi,const char* buf, ulong event_len)
 
 void end_relay_log_info(Relay_log_info* rli)
 {
+  mysql_mutex_t *log_lock;
   DBUG_ENTER("end_relay_log_info");
 
   if (!rli->inited)
@@ -6007,8 +6008,11 @@ void end_relay_log_info(Relay_log_info* rli)
     rli->cur_log_fd = -1;
   }
   rli->inited = 0;
+  log_lock= rli->relay_log.get_log_lock();
+  mysql_mutex_lock(log_lock);
   rli->relay_log.close(LOG_CLOSE_INDEX | LOG_CLOSE_STOP_EVENT);
   rli->relay_log.harvest_bytes_written(&rli->log_space_total);
+  mysql_mutex_unlock(log_lock);
   /*
     Delete the slave's temporary tables from memory.
     In the future there will be other actions than this, to ensure persistance