In the Linux kernel, the following vulnerability has been resolved:
drm/vkms: Fix null-ptr-deref in vkms_release()
A null-ptr-deref is triggered when it tries to destroy the workqueue in
vkms->output.composer_workq in vkms_release().
KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f]
CPU: 5 PID: 17193 Comm: modprobe Not tainted 6.0.0-11331-gd465bff130bf #24
RIP: 0010:destroy_workqueue+0x2f/0x710
...
Call Trace:
<TASK>
? vkms_config_debugfs_init+0x50/0x50 [vkms]
__devm_drm_dev_alloc+0x15a/0x1c0 [drm]
vkms_init+0x245/0x1000 [vkms]
do_one_initcall+0xd0/0x4f0
do_init_module+0x1a4/0x680
load_module+0x6249/0x7110
__do_sys_finit_module+0x140/0x200
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
The reason is that an OOM happened which triggers the destroy of the
workqueue, however, the workqueue is alloced in the later process,
thus a null-ptr-deref happened. A simple call graph is shown as below:
vkms_init()
vkms_create()
devm_drm_dev_alloc()
__devm_drm_dev_alloc()
devm_drm_dev_init()
devm_add_action_or_reset()
devm_add_action() # an error happened
devm_drm_dev_init_release()
drm_dev_put()
kref_put()
drm_dev_release()
vkms_release()
destroy_workqueue() # null-ptr-deref happened
vkms_modeset_init()
vkms_output_init()
vkms_crtc_init() # where the workqueue get allocated
Fix this by checking if composer_workq is NULL before passing it to
the destroy_workqueue() in vkms_release().
Metrics
Affected Vendors & Products
| Vendors | Products |
|---|---|
| Linux |
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No data.
No data.
References
History
Thu, 18 Sep 2025 12:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
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| Vendors & Products |
Linux
Linux linux Kernel |
Thu, 18 Sep 2025 00:15:00 +0000
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| References |
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| Metrics |
threat_severity
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cvssV3_1
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Wed, 17 Sep 2025 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: drm/vkms: Fix null-ptr-deref in vkms_release() A null-ptr-deref is triggered when it tries to destroy the workqueue in vkms->output.composer_workq in vkms_release(). KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f] CPU: 5 PID: 17193 Comm: modprobe Not tainted 6.0.0-11331-gd465bff130bf #24 RIP: 0010:destroy_workqueue+0x2f/0x710 ... Call Trace: <TASK> ? vkms_config_debugfs_init+0x50/0x50 [vkms] __devm_drm_dev_alloc+0x15a/0x1c0 [drm] vkms_init+0x245/0x1000 [vkms] do_one_initcall+0xd0/0x4f0 do_init_module+0x1a4/0x680 load_module+0x6249/0x7110 __do_sys_finit_module+0x140/0x200 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 The reason is that an OOM happened which triggers the destroy of the workqueue, however, the workqueue is alloced in the later process, thus a null-ptr-deref happened. A simple call graph is shown as below: vkms_init() vkms_create() devm_drm_dev_alloc() __devm_drm_dev_alloc() devm_drm_dev_init() devm_add_action_or_reset() devm_add_action() # an error happened devm_drm_dev_init_release() drm_dev_put() kref_put() drm_dev_release() vkms_release() destroy_workqueue() # null-ptr-deref happened vkms_modeset_init() vkms_output_init() vkms_crtc_init() # where the workqueue get allocated Fix this by checking if composer_workq is NULL before passing it to the destroy_workqueue() in vkms_release(). | |
| Title | drm/vkms: Fix null-ptr-deref in vkms_release() | |
| References |
|
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published: 2025-09-17T14:56:24.889Z
Updated: 2025-09-17T14:56:24.889Z
Reserved: 2025-09-17T14:53:06.995Z
Link: CVE-2022-50369
Vulnrichment
No data.
NVD
Status : Awaiting Analysis
Published: 2025-09-17T15:15:35.830
Modified: 2025-09-18T13:43:34.310
Link: CVE-2022-50369
Redhat