In the Linux kernel, the following vulnerability has been resolved:
drm/vc4: Use managed KMS polling to fix UAF on unbind
vc4_kms_load() calls drm_kms_helper_poll_init() but the driver provides
no matching drm_kms_helper_poll_fini(). The output poll work stays
scheduled after unbind and runs on the freed drm_device:
# modprobe vc4; rmmod vc4; sleep 10
BUG: KASAN: slab-use-after-free in delayed_work_timer_fn
BUG: KASAN: slab-use-after-free in drm_client_dev_hotplug [drm]
Workqueue: events output_poll_execute [drm_kms_helper]
Allocated by task 171: __devm_drm_dev_alloc
Freed by task 262 (rmmod): drm_dev_put / component_del
Use drmm_kms_helper_poll_init() so polling is finalized with the device,
as other drivers do.
drm/vc4: Use managed KMS polling to fix UAF on unbind
vc4_kms_load() calls drm_kms_helper_poll_init() but the driver provides
no matching drm_kms_helper_poll_fini(). The output poll work stays
scheduled after unbind and runs on the freed drm_device:
# modprobe vc4; rmmod vc4; sleep 10
BUG: KASAN: slab-use-after-free in delayed_work_timer_fn
BUG: KASAN: slab-use-after-free in drm_client_dev_hotplug [drm]
Workqueue: events output_poll_execute [drm_kms_helper]
Allocated by task 171: __devm_drm_dev_alloc
Freed by task 262 (rmmod): drm_dev_put / component_del
Use drmm_kms_helper_poll_init() so polling is finalized with the device,
as other drivers do.
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Affected Vendors & Products
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Fixes
Solution
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Workaround
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References
History
Tue, 06 Oct 2026 09:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: drm/vc4: Use managed KMS polling to fix UAF on unbind vc4_kms_load() calls drm_kms_helper_poll_init() but the driver provides no matching drm_kms_helper_poll_fini(). The output poll work stays scheduled after unbind and runs on the freed drm_device: # modprobe vc4; rmmod vc4; sleep 10 BUG: KASAN: slab-use-after-free in delayed_work_timer_fn BUG: KASAN: slab-use-after-free in drm_client_dev_hotplug [drm] Workqueue: events output_poll_execute [drm_kms_helper] Allocated by task 171: __devm_drm_dev_alloc Freed by task 262 (rmmod): drm_dev_put / component_del Use drmm_kms_helper_poll_init() so polling is finalized with the device, as other drivers do. | |
| Title | drm/vc4: Use managed KMS polling to fix UAF on unbind | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Projects
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MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-06T08:46:05.957Z
Reserved: 2026-09-25T10:25:14.338Z
Link: CVE-2026-98309
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-06T09:18:22.300
Modified: 2026-10-06T09:18:22.300
Link: CVE-2026-98309
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.