CVE-2022-48816

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

SUNRPC: lock against ->sock changing during sysfs read

->sock can be set to NULL asynchronously unless ->recv_mutex is held.

So it is important to hold that mutex. Otherwise a sysfs read can

trigger an oops.

Commit 17f09d3f619a ("SUNRPC: Check if the xprt is connected before

handling sysfs reads") appears to attempt to fix this problem, but it

only narrows the race window.