CVE-2026-68429

In the Linux kernel, the following vulnerability has been resolved: drm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe() A hotplug or link-loss event can tear down the MST topology (setting mgr->mst_state = false and mgr->mst_primary = NULL) concurrently with a caller invoking drm_dp_mst_topology_queue_probe(). Since the check is already performed under mgr->lock, the condition is not a programming error but a valid race -- the topology was valid when the caller decided to call this function, but was torn down before the lock was acquired. Replace the drm_WARN_ON() with a graceful early return. This eliminates spurious kernel warnings and the resulting compositor crashes observed when connecting/disconnecting DP MST monitors, while keeping the correct behavior of doing nothing when MST is not active. A drm_dbg_mst() trace is added so the skipped probe remains observable under MST debug logging. The existing WARN_ON(mgr->mst_primary) in drm_dp_mst_topology_mgr_set_mst() already catches the case where the topology is initialized twice, so no diagnostic coverage is lost.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/4ed6d08c4a59ee6a8cb806347f6d9873de5d229e
https://git.kernel.org/stable/c/613059875958e7b217b250ed14c3b189f9488421
https://git.kernel.org/stable/c/8c6d84a54823cd839e6ce22af559925f1320c310
https://git.kernel.org/stable/c/afdff9103818656627920c21822e48a6dae2906f
https://git.kernel.org/stable/c/b1d05cc61dfa6c4bd5e67855bec6a03e955f512d

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-12 00:17

Updated : 2026-08-17 06:17

NVD link : CVE-2026-68429

Mitre link : CVE-2026-68429

CVE.ORG link : CVE-2026-68429

JSON object : View

Products Affected

No product.

CWE

No CWE.

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