CVE-2026-93067
Description
In the Linux kernel, the following vulnerability has been resolved: drm/bridge: tc358767: clamp the reported AUX read size to the request tc_aux_transfer() clamps an AUX read to the payload limit: size_t size = min_t(size_t, DP_AUX_MAX_PAYLOAD_BYTES - 1, msg->size); After the transfer it replaces size with the byte count the controller reports in AUX_BYTES: if (size) size = FIELD_GET(AUX_BYTES, auxstatus); AUX_BYTES is GENMASK(15, 8), so it can be up to 255. Nothing clamps it back to the request. tc_aux_read_data() reads that many bytes into the 16-byte auxrdata stack buffer, then copies them into the caller buffer. A reported count of 255 makes the read run to 256 bytes and overruns both. The controller should never report more than it was asked to transfer, so this is defense in depth rather than a live hole. The reported count is only lightly trusted, and the check is cheap. Clamp it back to the request, the same way ti-sn65dsi86 does in commit aca58eac52b8 ("drm/bridge: ti-sn65dsi86: Never store more than msg->size bytes in AUX xfer").
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://git.kernel.org/stable/c/33c0b072e31dee98a754d9bd01800359dfeb9e8f
- https://git.kernel.org/stable/c/424b762cc26d512e3e7421e57e41b4b55be2400b
- https://git.kernel.org/stable/c/57c567e0e8aa76f6e3e8f39d7f40c20bc37e76af
- https://git.kernel.org/stable/c/982caa744fce79d18f2920382aaeb0da821a6e73
- https://git.kernel.org/stable/c/9ff718df547372d70ca20ad8e66a3fb1300936b2
- https://git.kernel.org/stable/c/dd6274706bec30d005bff0587a4262d01dc2775a
- https://git.kernel.org/stable/c/ebf00c51c9ac9188e2806a2b842418805ee879be
- https://git.kernel.org/stable/c/ec6444a00c49e6c2b5e9a507272a28126677f9ee
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.