[CVE-2026-68382][MODERATE 7.0] drm/xe/guc: Hold device ref until queue teardown completes [ Upstream

[CVE-2026-68382][MODERATE 7.0] drm/xe/guc: Hold device ref until queue teardown completes [ Upstream

[AL-KERNEL]

CVE: CVE-2026-68382
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: drm/xe/guc: Hold device ref until queue teardown completes [ Upstream
Commit: 03d6f83979b0d75a0b0893dfe1735ec93facf515
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=03d6f83979b0d75a0b0893dfe1735ec93facf515
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68382
Analysis date: Mon, 10 Aug 2026 16:46:15 -0400
ActionableScore: 5
ActionableScore lower bound: 3
Actionable bucket: Actionable Moderate at minimum
Manual review required: NO

Summary:
A local DRM Xe GuC queue teardown lifetime bug can allow async destroy work to overlap with final drm_device cleanup, causing a workqueue self-deadlock and denial of service, with weak additional concern due to nearby device-lifetime and prior UAF-related queue destruction logic.

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ABOUT THIS REPORT
======================================================================

The original Linux kernel CVE announcement for CVE-2026-68382 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68382

The original announcement does not normally provide a security severity
estimate, CVSS assessment, or enough information to determine whether the
reported kernel bug represents a practically relevant security issue.

This report was generated by AL-KERNEL, an AI-assisted Linux kernel
vulnerability analysis system developed by Alexander Larkin. It combines
an autonomous classifier with LLM-assisted technical analysis and a
separate ActionableScore mechanism.

The purpose of this report is to prioritize Linux kernel CVEs before
manual review, identify cases that require prompt investigation, and
support automatic closure of issues that are unlikely to have meaningful
security impact.

Published priority for this report: MODERATE 7.0
Manual review required: NO

A detailed explanation of the methodology and priority rules is included
at the end of this message.

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AL-KERNEL CLASSIFICATION RESULT
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CVE-2026-68382	MODERATE	CHECK WITH IMPACT FROM ORIG NN MODERATE	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H';*CWE-833;CWE-362;*CWE-416;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.8';DESCR 'GuC exec queue teardown in drm xe can run asynchronously while the drm_device lifetime is ending. If the final device reference is dropped from a destroy worker, managed drm cleanup can try to drain the same destroy workqueue, causing a self dependency deadlock and a local denial of service. The bug is a teardown ordering and lifetime race rather than a directly demonstrated arbitrary write. For the CVSS the PR:L is used for the paranoid score because a local user with access to the DRM render device may be able to create and destroy GPU queues and influence the asynchronous teardown path, while full administrative control is not always required in desktop or GPU compute deployments. The issue is not network reachable. Impact is at least denial of service through a stuck cleanup or unload path, with limited confidentiality or integrity impact only in the paranoid interpretation because the fix addresses device lifetime around pending async work.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate at minimum (with actual score 4)  SKIP CVE-2026-68382 UNKNOWN SKIP The Fixes patch not applied yet, so unlikely that actual: 2d2be279f1ca9e7288282d4214f16eea8a727cdb YES  NO NO unknown 	MAYBE	DEADLOCK INIT NOMEMCHK UAF HARDWARE  DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5	-	-	checked

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ACTIONABLESCORE ANALYSIS
======================================================================

ActionableScore=5
ActionableScoreLower=3

## 1. ActionableScore

* Conservative score: 3
* Paranoid score: 5
* Final recommended bucket: **Actionable Moderate at minimum**

## 2. Signal breakdown

Conservative signals:

* Local unprivileged trigger: +1. A local user with access to the DRM render node may be able to create and destroy GuC exec queues.
* Real lifetime corruption: +1. The fix changes drm_device reference lifetime around asynchronous queue teardown.
* Reliable kernel crash / strong DoS: +1. The described failure is a workqueue self-deadlock during managed DRM cleanup.
* Broad/default/common subsystem exposure: +1. DRM render nodes are commonly exposed to local users on systems with supported Intel Xe GPUs.
* Hard or unreliable race / special timing required: -1. The problematic condition depends on async teardown overlapping with final device cleanup.

Paranoid additional signals:

* Memory corruption, weak/indirect corruption candidate: +1. The patch is primarily a deadlock fix, but it is a device lifetime ordering bug and references an earlier UAF-related queue destruction fix.
* Privileged kernel/device-management lifetime path: +1. The affected objects are DRM device and GuC queue lifetime objects in a trusted GPU driver teardown path.

Not awarded:

* No remote/network trigger.
* No strong LPE plausibility.
* No strong memory corruption primitive.
* No arbitrary write, controlled reclaim, callback takeover, or type confusion is shown by the patch.

## 3. Reachability analysis

The most realistic trigger is local. A user with DRM render-node access may be able to create and destroy GPU execution queues and influence async teardown timing. However, the fully demonstrated deadlock involves final drm_device cleanup, PCI remove, hot-unbind, unload, or similar teardown paths, which are often administrator controlled.

Namespaces and containers may matter if GPU render devices are passed through or exposed to containers. In that case, a reduced-privilege container or service account with render-node access could influence queue lifetime without having full host root. The path is not network reachable. It is hardware and driver dependent, requiring the Intel Xe DRM driver and GuC submission path.

Call-site confidence: high, because the patch includes the relevant queue init, async destroy, fini, module workqueue, and PCI remove changes.

## 4. Severity interpretation

This behaves primarily like an actionable local DoS / lifetime-ordering issue, not a proven Important-class memory corruption vulnerability. The demonstrated impact is a deadlock when async destroy work interacts with drm managed cleanup.

The paranoid score is higher because the bug sits in queue teardown and drm_device lifetime management, and the fixed commit references a prior UAF around queue destruction. Still, the patch does not show attacker-controlled reclaim, stale object replacement, write-after-free, function pointer control, or arbitrary memory corruption. Therefore it should not be treated as a strong LPE candidate without manual source review.

## 5. One-sentence report phrase

A local DRM Xe GuC queue teardown lifetime bug can allow async destroy work to overlap with final drm_device cleanup, causing a workqueue self-deadlock and denial of service, with weak additional concern due to nearby device-lifetime and prior UAF-related queue destruction logic.

## 6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Manual review is recommended because this is a local async lifetime race in GPU queue teardown with possible UAF relevance, but the provided patch mainly demonstrates deadlock and does not show a concrete privilege-escalation primitive.

======================================================================
UPSTREAM PATCH SUMMARY
======================================================================

Patch: drm/xe/guc: Hold device ref until queue teardown completes [ Upstream
Commit: 03d6f83979b0d75a0b0893dfe1735ec93facf515
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=03d6f83979b0d75a0b0893dfe1735ec93facf515

Changed files:
  drivers/gpu/drm/xe/xe_device.c
  drivers/gpu/drm/xe/xe_device_types.h
  drivers/gpu/drm/xe/xe_guc_submit.c
  drivers/gpu/drm/xe/xe_guc_types.h
  drivers/gpu/drm/xe/xe_module.c
  drivers/gpu/drm/xe/xe_module.h
  drivers/gpu/drm/xe/xe_pci.c

Diff excerpt:

Not included in this email. See the upstream URL for the full patch.

Full patch:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=03d6f83979b0d75a0b0893dfe1735ec93facf515

======================================================================
DETAILED REPORT METHODOLOGY
======================================================================

The original Linux kernel CVE announcement for CVE-2026-68382 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68382

The original CVE announcement normally does not include a security-level
estimate. In particular, it may not contain a CVSS assessment, an impact
level, or enough information to determine whether the reported bug is a
practically relevant security issue. One purpose of this parallel CVE list
is to provide that missing technical and prioritization information.

The original goal of the AL-KERNEL project was to prioritize Linux kernel
CVE analysis automatically before manual review. The system can also help
identify non-security issues that may be suitable for automatic closure.

This report was generated by AL-KERNEL, an AI-assisted Linux kernel
vulnerability analysis system developed by Alexander Larkin.

The first analysis stage combines an autonomous classifier with additional
LLM-based analysis. The autonomous classifier runs locally on a CPU and is
based on a backpropagation neural network. Together, these mechanisms
produce a technical vulnerability description, identify likely weakness
types, estimate CVSS severity, and provide input for ActionableScore.

Two CVSS estimates are retained because incomplete kernel vulnerability
information often permits more than one defensible interpretation:

  Conservative CVSS vector: AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H
  The Best / paranoid CVSS score: 5.8

The conservative vector represents a lower-impact interpretation.
The Best/paranoid vector intentionally represents a plausible upper-bound
interpretation and should not automatically be treated as demonstrated
real-world impact.

CVSS may also need to be adjusted for a particular Linux deployment,
because actual reachability, privileges, enabled kernel configuration,
hardware, namespaces, exposed device nodes, and other environmental
conditions can differ significantly between systems.

A separate ActionableScore mechanism evaluates practical remediation
urgency. Its analysis may include reachability, attack prerequisites,
subsystem exposure, memory-corruption characteristics, denial-of-service
reliability, and possible confidentiality, integrity, or
privilege-escalation impact.

  Conservative ActionableScore: 3
  Paranoid ActionableScore: 5

The final base severity is taken directly from the second tab-separated
field of the AL-KERNEL classification result. ActionableScore does not
replace or independently override that final AL-KERNEL decision, and
if ActionableScore adjusted impact level of ALKERNEL, then you would see
self-readable flags above like INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7.

For an AL-KERNEL result of MODERATE, this report uses the following
additional presentation split:

  ActionableScore below 5   -> MODERATE REGULAR
  ActionableScore 5 or more -> MODERATE 7.0

The distinction between MODERATE REGULAR and MODERATE 7.0 makes it
possible to identify Moderate issues that should receive manual analysis
and fixes before lower-priority MODERATE REGULAR issues. In many cases,
MODERATE REGULAR fixes may wait for a later rebase or routine update.

There is one override in which MODERATE REGULAR becomes MODERATE 7.0
even when the ActionableScore is below 5. When the AL-KERNEL result
contains the KPANIC flag, a MODERATE result is always presented as
MODERATE 7.0. The KPANIC flag selected with few regexps without
usage of AI at all, so it helps to detect cases when Kernel Crash happens
and similar (to filter False-Negative results from the LLM usage).

KPANIC indicates that a reliable kernel crash, kernel panic, or similarly
serious kernel availability impact was identified by the classification
workflow.

AL-KERNEL base severity for this report: MODERATE
KPANIC detected for this report: NO
Published priority for this report (same as in Subject): MODERATE 7.0

These results are intended to support engineering triage. They are
machine-generated estimates, and cases marked for manual review should
be validated by a human security engineer before final disposition.
For more info read docs linked from here: https://kernelcve.org/
(and you can submit you own patch there to generate such a report
for non-existant CVE-id yet).

Note that in many cases this AI tool selects higher severity, than
real is (means you can expect Importants instead of Moderate 7.0 or
Moderates 7.0 instead of regular Moderates). If you see such cases,
please use reply email interface to add additional manual analyses
info to this particular CVE.
And please, please, let me know when you see Lows instead of Importants
or Important instead of Low (because particular for such cases I
need to tune this AI tool to make it better for this one and next similar).
My contact email for such notifications is alexanjelausa@gmail.com (and both
send reply to CVE record itself too and see "reply" button below for howto reply).