CVE-2026-63795 9p: avoid putting oldfid in p9_client_walk() error path

In the Linux kernel, the following vulnerability has been resolved: 9p: avoid putting oldfid in p9clientwalk error path When p9clientwalk is called with clone set to false, fid aliases oldfid. If the walk subsequently fails after the request has been sent, the error path jumps to clunkfid, which...