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.

1 files changed, 17 insertions, 19 deletions

diff --git a/sql/log.cc b/sql/log.cc
index bdd60b4d420..e99eefe4970 100644
--- a/sql/log.cc
+++ b/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 @@ end:
                      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