CVE-2022-49103

In the Linux kernel, the following vulnerability has been resolved:

NFSv4.2: fix reference count leaks in _nfs42_proc_copy_notify()

[You don't often get email from xiongx18@fudan.edu.cn. Learn why this is important at http://aka.ms/LearnAboutSenderIdentification.]

The reference counting issue happens in two error paths in the
function _nfs42_proc_copy_notify(). In both error paths, the function
simply returns the error code and forgets to balance the refcount of
object `ctx`, bumped by get_nfs_open_context() earlier, which may
cause refcount leaks.

Fix it by balancing refcount of the `ctx` object before the function
returns in both error paths.