CVE-2025-22038 ksmbd: validate zero num_subauth before sub_auth is accessed

In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate zero numsubauth before subauth is accessed Access psid-subauthpsid-numsubauth - 1 without checking if numsubauth is non-zero leads to an out-of-bounds read. This patch adds a validation step to ensure numsubauth !...