Bug #24557925: MYSQL_CONFIG_EDITOR CAN MAKE SERVER UNBOOTABLE

By default all mysys based programs are sourcing the login file.
The server should not be doing this since it's not a client program.

Thus added a new global to mysys, that, when set to FALSE disables
the sourcing of the login path file.
And then changed mysqld to set that variable to FALSE from its
mysys default TRUE.

Added a test case.

Author: gkodinov

include/my_default.h

@@ -25,6 +25,7 @@ extern const char *my_defaults_extra_file;
 extern const char *my_defaults_group_suffix;
 extern const char *my_defaults_file;
 extern my_bool my_getopt_use_args_separator;
+extern my_bool my_defaults_read_login_file;
 
 /* Define the type of function to be passed to process_default_option_files */
 typedef int (*Process_option_func)(void *ctx, const char *group_name,

mysql-test/r/mysql_config_editor.result

@@ -267,3 +267,10 @@ mysqld is alive
 # normally.
 mysqld is alive
 #### End of test ####
+#
+# Bug #24557925: MYSQL_CONFIG_EDITOR CAN MAKE SERVER UNBOOTABLE
+#
+# Restarting the server. Should work
+# Cleanup
+/home/gkodinov/work/B24557925-5.6/client//mysql_config_editor remove --login-path=mysqld
+# End of 5.6 tests

mysql-test/t/mysql_config_editor.test

@@ -203,3 +203,19 @@ DROP USER test_user1, test_user2;
 
 --echo #### End of test ####
 
+
+--echo #
+--echo # Bug #24557925: MYSQL_CONFIG_EDITOR CAN MAKE SERVER UNBOOTABLE
+--echo #
+
+
+--exec $MYSQL_CONFIG_EDITOR set --login-path=mysqld --host=test_user5
+
+--echo # Restarting the server. Should work
+--source include/restart_mysqld.inc
+
+--echo # Cleanup
+--echo $MYSQL_CONFIG_EDITOR remove --login-path=mysqld
+--remove_file $MYSQL_TEST_LOGIN_FILE
+
+--echo # End of 5.6 tests

mysys_ssl/my_default.cc

@@ -578,6 +578,8 @@ int load_defaults(const char *conf_file, const char **groups,
   return my_load_defaults(conf_file, groups, argc, argv, &default_directories);
 }
 
+/** A global to turn off or on reading the mylogin file. On by default */
+my_bool my_defaults_read_login_file= TRUE;
 /*
   Read options from configurations files
 
@@ -665,16 +667,18 @@ int my_load_defaults(const char *conf_file, const char **groups,
     DBUG_RETURN(error);
   }
 
-  /* Read options from login group. */
-  if (my_default_get_login_file(my_login_file, sizeof(my_login_file)) &&
-      (error= my_search_option_files(my_login_file,argc, argv, &args_used,
+  if (my_defaults_read_login_file)
+  {
+    /* Read options from login group. */
+    if (my_default_get_login_file(my_login_file, sizeof(my_login_file)) &&
+      (error= my_search_option_files(my_login_file, argc, argv, &args_used,
                                      handle_default_option, (void *) &ctx,
                                      dirs, true, found_no_defaults)))
-  {
-    free_root(&alloc,MYF(0));
-    DBUG_RETURN(error);
+    {
+      free_root(&alloc, MYF(0));
+      DBUG_RETURN(error);
+    }
   }
-
   /*
     Here error contains <> 0 only if we have a fully specified conf_file
     or a forced default file

sql/mysqld.cc

@@ -5261,6 +5261,7 @@ int mysqld_main(int argc, char **argv)
   orig_argc= argc;
   orig_argv= argv;
   my_getopt_use_args_separator= TRUE;
+  my_defaults_read_login_file= FALSE;
   if (load_defaults(MYSQL_CONFIG_NAME, load_default_groups, &argc, &argv))
     return 1;
   my_getopt_use_args_separator= FALSE;