check_mysql: Fix segfault with old slaves (#2696823 - Oskar Ahner)

1 files changed, 2 insertions, 1 deletions

diff --git a/plugins/check_mysql.c b/plugins/check_mysql.c
index 119ce0af..689648eb 100644
--- a/plugins/check_mysql.c
+++ b/plugins/check_mysql.c
@@ -177,13 +177,14 @@ main (int argc, char **argv)
                                         continue;
                                 }
                         }
+
                         if ((slave_io_field < 0) || (slave_sql_field < 0) || (num_fields == 0)) {
                                 mysql_free_result (res);
                                 mysql_close (&mysql);
                                 die (STATE_CRITICAL, "Slave status unavailable\n");
                         }
 
-                        snprintf (slaveresult, SLAVERESULTSIZE, "Slave IO: %s Slave SQL: %s Seconds Behind Master: %s", row[slave_io_field], row[slave_sql_field], row[seconds_behind_field]);
+                        snprintf (slaveresult, SLAVERESULTSIZE, "Slave IO: %s Slave SQL: %s Seconds Behind Master: %s", row[slave_io_field], row[slave_sql_field], seconds_behind_field!=-1?row[seconds_behind_field]:"Unknown");
                         if (strcmp (row[slave_io_field], "Yes") != 0 || strcmp (row[slave_sql_field], "Yes") != 0) {
                                 mysql_free_result (res);
                                 mysql_close (&mysql);