CVE-2026-31477 ksmbd: fix memory leaks and NULL deref in smb2_lock()

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix memory leaks and NULL deref in smb2lock smb2lock has three error handling issues after listdel detaches smblock from locklist at nocheckcl: 1 If vfslockfile returns an unexpected error in the non-UNLOCK path, goto out...