Description
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.
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.
Published:
2026-08-12
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
No analysis available yet.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
||||||||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
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References
History
Wed, 12 Aug 2026 00:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Title | drm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe() | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-08-12T00:07:14.640Z
Reserved: 2026-07-30T09:28:09.393Z
Link: CVE-2026-68429
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-08-12T00:17:42.940
Modified: 2026-08-12T00:17:42.940
Link: CVE-2026-68429
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.