In the Linux kernel, the following vulnerability has been resolved:
ksmbd: safely discard unregistered deferred locks
When vfs_lock_file() defers a lock, smb2_lock() puts its ksmbd_lock on
rollback_list before allocating and registering the asynchronous work.
If either operation fails, rollback assumes that smb_lock->conn is
initialized and dereferences NULL. The deferred file_lock also remains
linked into the VFS blocked-lock state while it is freed.
Keep the lock off rollback_list until async setup succeeds. On setup
failures, explicitly unblock and wake the deferred lock before freeing it
and its ksmbd wrapper.
