branches/zip:

 
Bugfix: Lock the MySQL mutex LOCK_thread_count before accessing
trx->mysql_query_str to avoid race conditions where MySQL sets it to
NULL after we have checked that it is not NULL and before we access it.
 
Approved by:	Marko

trx/trx0i_s.c

@@ -19,6 +19,7 @@ Created July 17, 2007 Vasil Dimov
 #include "buf0buf.h"
 #include "dict0dict.h"
 #include "ha0storage.h"
+#include "ha_prototypes.h"
 #include "hash0hash.h"
 #include "lock0iter.h"
 #include "lock0lock.h"
@@ -1138,6 +1139,9 @@ trx_i_s_possibly_fetch_data_into_cache(
 		return(1);
 	}
 
+	/* We are going to access trx->query in all transactions */
+	innobase_mysql_prepare_print_arbitrary_thd();
+
 	/* We need to read trx_sys and record/table lock queues */
 	mutex_enter(&kernel_mutex);
 
@@ -1145,6 +1149,8 @@ trx_i_s_possibly_fetch_data_into_cache(
 
 	mutex_exit(&kernel_mutex);
 
+	innobase_mysql_end_print_arbitrary_thd();
+
 	return(0);
 }