[PATCH 6.1.y 0/2] drm/i915/hdcp: guard both capability checks

[Artem Dinaburg <artem@trailofbits.com>]

Hi Greg, Sasha, and i915 maintainers,

Patch 1 alone is not enough on 6.1.y: intel_hdcp_info() calls
intel_hdcp_capable() and then intel_hdcp2_capable(), so the debugfs NULL
dereference moves to the second call. Patch 2 is the companion fix that
path needs, a backport of upstream commit d34f4f058edf ("drm/i915/hdcp:
Add encoder check in hdcp2_get_capability") with the guard in the common
intel_hdcp2_capable() helper, where 6.1.y still does the lookup. This
mirrors the 2-patch series picked up for 6.6.y, and both fixes are
already present in 6.12.y, 6.18.y, and 7.2.y. Could you please queue both
patches for 6.1.y?

AI assistance: An LLM helped adapt and validate both patches; I reviewed
the resulting code and validation evidence.

Thanks,
Artem Dinaburg

Series:
  1. drm/i915/hdcp: Add encoder check in intel_hdcp_get_capability
  2. drm/i915/hdcp: Add encoder check in hdcp2_get_capability