{"id":"CVE-2026-68429","title":"drm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe()\n\nA hotplug or link-loss event can tear down the MST topology\n(setting mgr->mst_sta…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 5f57a96e92c60f62da91d58ceb5e5acd40e7d594 < b1d05cc61dfa6c4bd5e67855bec6a03e955f512d","Linux >= dbaeef363ea54f4c18112874b77503c72ba60fec < 4ed6d08c4a59ee6a8cb806347f6d9873de5d229e","Linux >= dbaeef363ea54f4c18112874b77503c72ba60fec < 8c6d84a54823cd839e6ce22af559925f1320c310","Linux >= dbaeef363ea54f4c18112874b77503c72ba60fec < afdff9103818656627920c21822e48a6dae2906f","Linux >= dbaeef363ea54f4c18112874b77503c72ba60fec < 613059875958e7b217b250ed14c3b189f9488421","Linux >= 6.6.86 < 6.6.148","Linux 6.12"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:49:22.194487Z"},"published":"2026-08-12","updated":"2026-11-06","sourceUpdated":"2026-11-06T16:55:16.587Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-68429","references":[{"url":"https://git.kernel.org/stable/c/b1d05cc61dfa6c4bd5e67855bec6a03e955f512d"},{"url":"https://git.kernel.org/stable/c/4ed6d08c4a59ee6a8cb806347f6d9873de5d229e"},{"url":"https://git.kernel.org/stable/c/8c6d84a54823cd839e6ce22af559925f1320c310"},{"url":"https://git.kernel.org/stable/c/afdff9103818656627920c21822e48a6dae2906f"},{"url":"https://git.kernel.org/stable/c/613059875958e7b217b250ed14c3b189f9488421"}],"tags":["cve.org"],"epss":0.00168,"epssPercentile":0.06219,"ingestedAt":"2026-11-06T18:00:12.608Z","slug":"CVE-2026-68429","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ndrm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe()\n\nA hotplug or link-loss event can tear down the MST topology\n(setting mgr->mst_state = false and mgr->mst_primary = NULL) concurrently\nwith a caller invoking drm_dp_mst_topology_queue_probe(). Since the check\nis already performed under mgr->lock, the condition is not a programming\nerror but a valid race -- the topology was valid when the caller decided\nto call this function, but was torn down before the lock was acquired.\n\nReplace the drm_WARN_ON() with a graceful early return. This eliminates\nspurious kernel warnings and the resulting compositor crashes observed\nwhen connecting/disconnecting DP MST monitors, while keeping the correct\nbehavior of doing nothing when MST is not active. A drm_dbg_mst() trace\nis added so the skipped probe remains observable under MST debug logging.\n\nThe existing WARN_ON(mgr->mst_primary) in drm_dp_mst_topology_mgr_set_mst()\nalready catches the case where the topology is initialized twice, so no\ndiagnostic coverage is lost.\n\n## Affected\n\n- `Linux >= 5f57a96e92c60f62da91d58ceb5e5acd40e7d594 < b1d05cc61dfa6c4bd5e67855bec6a03e955f512d`\n- `Linux >= dbaeef363ea54f4c18112874b77503c72ba60fec < 4ed6d08c4a59ee6a8cb806347f6d9873de5d229e`\n- `Linux >= dbaeef363ea54f4c18112874b77503c72ba60fec < 8c6d84a54823cd839e6ce22af559925f1320c310`\n- `Linux >= dbaeef363ea54f4c18112874b77503c72ba60fec < afdff9103818656627920c21822e48a6dae2906f`\n- `Linux >= dbaeef363ea54f4c18112874b77503c72ba60fec < 613059875958e7b217b250ed14c3b189f9488421`\n- `Linux >= 6.6.86 < 6.6.148`\n- `Linux 6.12`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}