fsnotify: Allocate overflow events with proper type
Commit 7053aee26a35 "fsnotify: do not share events between notification
groups" used overflow event statically allocated in a group with the
size of the generic notification event. This causes problems because
some code looks at type specific parts of event structure and gets
confused by a random data it sees there and causes crashes.
Fix the problem by allocating overflow event with type corresponding to
the group type so code cannot get confused.
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/notify/group.c b/fs/notify/group.c
index ee674fe..ad19959 100644
--- a/fs/notify/group.c
+++ b/fs/notify/group.c
@@ -55,6 +55,13 @@
/* clear the notification queue of all events */
fsnotify_flush_notify(group);
+ /*
+ * Destroy overflow event (we cannot use fsnotify_destroy_event() as
+ * that deliberately ignores overflow events.
+ */
+ if (group->overflow_event)
+ group->ops->free_event(group->overflow_event);
+
fsnotify_put_group(group);
}
@@ -99,7 +106,6 @@
INIT_LIST_HEAD(&group->marks_list);
group->ops = ops;
- fsnotify_init_event(&group->overflow_event, NULL, FS_Q_OVERFLOW);
return group;
}