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/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 6528b5a..78a2ca3 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -633,11 +633,23 @@
static struct fsnotify_group *inotify_new_group(unsigned int max_events)
{
struct fsnotify_group *group;
+ struct inotify_event_info *oevent;
group = fsnotify_alloc_group(&inotify_fsnotify_ops);
if (IS_ERR(group))
return group;
+ oevent = kmalloc(sizeof(struct inotify_event_info), GFP_KERNEL);
+ if (unlikely(!oevent)) {
+ fsnotify_destroy_group(group);
+ return ERR_PTR(-ENOMEM);
+ }
+ group->overflow_event = &oevent->fse;
+ fsnotify_init_event(group->overflow_event, NULL, FS_Q_OVERFLOW);
+ oevent->wd = -1;
+ oevent->sync_cookie = 0;
+ oevent->name_len = 0;
+
group->max_events = max_events;
spin_lock_init(&group->inotify_data.idr_lock);