CVE-2026-68340: hwmon: occ: validate poll response sensor blocks

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

hwmon: occ: validate poll response sensor blocks

The OCC poll response parser walks a counted list of sensor data blocks. It used the static backing-array capacity as the parse boundary, but a transport response makes only datalength bytes current and valid. A truncated response can therefore make the parser consume a block header or block extent outside the current response.

Use datalength as the parent boundary, prove the fixed poll header and each current block header before reading them, and prove the complete block before advancing. Keep parsed sensor metadata local until the complete response has passed validation, then publish it. Propagate malformed-response errors before publishing the OCC as active.