CVE-2026-68277 drm/dp/mst: fix OOB reads on 2-byte fields in sideband reply parsers

In the Linux kernel, the following vulnerability has been resolved: drm/dp/mst: fix OOB reads on 2-byte fields in sideband reply parsers Three sideband reply parsers read 16-bit fields as: val = raw-msgidx msgidx+1; and check bounds only after the fact. When idx == raw-curlen, raw-msgidx+1 reads...