[CVE-2026-98671][LOW] iio: adc: sun4i-gpadc-iio: clean up on thermal zone registration failure

[CVE-2026-98671][LOW] iio: adc: sun4i-gpadc-iio: clean up on thermal zone registration failure

[AL-KERNEL]

CVE: CVE-2026-98671
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: iio: adc: sun4i-gpadc-iio: clean up on thermal zone registration failure
Commit: 1bad19e598cd77884d812fd2f88b05c635b5e7ad
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1bad19e598cd77884d812fd2f88b05c635b5e7ad
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98671
Analysis date: Fri, 23 Oct 2026 20:26:52 -0400
ActionableScore: 1
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
A failed thermal-zone registration can leave the sun4i GPADC IIO map registered and runtime PM enabled, causing an incomplete device-probe cleanup without demonstrated memory corruption or host-wide denial of service.

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

The original Linux kernel CVE announcement for CVE-2026-98671 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98671

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: LOW
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-2026-98671	LOW	https://www.kernelcve.org/list/?q=CVE-2026-98671 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT LOW AEGIS_AS=0 LEGACY=LOW RESULT=SAME (final reconciliation agrees; DECISION: both LOW)	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';CWE-459;*CWE-772;CWE-404;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '2.5';DESCR 'The sun4i gpadc driver can leave an IIO map registered and runtime PM enabled when thermal zone registration fails during probe. The demonstrated primitive is incomplete resource cleanup after a failed device initialization rather than memory corruption. The remaining state may retain resources or interfere with a later probe and device operation, but the patch does not establish an immediate system wide failure. For the CVSS the PR:L in the paranoid score covers environments where a reduced capability service account or container root can repeatedly rebind or reprobe the device. In normal deployments device probing and driver binding require administrative control, making PR:H more realistic. The issue is not network reachable and no UAF, OOB access, information disclosure, or privilege escalation path is supported by the affected control flow. Impact is limited to low availability risk for the affected device or subsystem. Automated impact decision path. The original SimpleNet classifier selected LOW. The primary LLM estimated paranoid CVSS 2.5 and the production ActionableScore returned 1 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. No severity changing production threshold or specialist override was recorded. The legacy KP specialist has no review artifact for this run. The legacy FD or DH downgrade specialist has no review artifact for this run. The independent weaker Aegis shadow evaluated CVSS 0.0 and ActionableScore 0 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was LOW. The shadow agreed with the final production impact and aggregation did not change that impact. The final reported impact is LOW.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1)	MAYBE	SIMPLEFIX ERRORPATH LINUS 	-	-	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=1
PrimitiveClass=NONE
RealUAF=NO
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=NO
ImportantCandidate=NO
ManualReview=NO
AutoDowngradeAllowed=YES
RequiresHostUID0=UNKNOWN
AuthorizationDecisionBypass=NO
ProtectedResourceImpact=NONE
B4PendingReview=NO
B4PendingConfirmed=NO

1. ActionableScore

* Raw conservative score: 1
* Conservative score: 1
* Raw paranoid score: 1
* Paranoid score: 1
* No floor or cap was applied.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* +1 Concrete persistent kernel resource cleanup defect. A thermal-zone registration failure bypasses `err_map`, leaving the IIO map registered and runtime PM enabled after probe failure.
* No strong DoS point. Host-wide exhaustion, kernel panic, or reliable accumulation through attacker-controlled retries is not established.
* No UAF, OOB access, repeated release, active-state corruption, authorization bypass, or shared-backing write is present.
* B5-R does not apply because there is no heap OOB write or retry-accumulated offset.
* B3-PENDING does not apply because no shared or file-backed storage is modified.
* B4-PENDING does not apply because no DENY-to-ALLOW authorization decision exists.
* No privilege penalty was applied because the complete attacker model is unresolved. The patch does not positively establish either host-admin-only triggering or below-host-admin triggering.

3. Reachability analysis

The defect occurs during `sun4i_gpadc_probe()` when `devm_thermal_of_zone_register()` fails after IIO map registration and runtime PM activation. Ordinary users cannot normally control platform-device probing, driver binding, or thermal-zone registration, but the supplied evidence does not establish that every possible failure requires an effective host administrator. Therefore `HostAdminRequired=UNKNOWN`.

No namespace-scoped interface, remote path, or attacker-controlled retry loop is shown. Relevant prerequisites include compatible sun4i GPADC hardware, the driver, thermal integration, and a thermal-zone registration failure. There is no race.

4. Primitive and severity interpretation

The exact defect is incomplete error-path cleanup. It retains registration and power-management state after failed initialization, but it does not establish memory corruption or post-lifetime access.

There is no stale object, no first operation that ends object lifetime, and no second lifetime or refcount mutation. The behavior therefore does not qualify as Class B or Class C corruption and is classified as `NONE`.

The demonstrated consequence is residual device-subsystem state and possible device-local availability degradation. System-wide resource exhaustion is speculative because repeatable attacker control over the failing probe path is not established. `ImportantCandidate=NO` and `AutoDowngradeAllowed=YES` because no unresolved corruption, ownership, or security-boundary primitive remains.

5. One-sentence report phrase

A failed thermal-zone registration can leave the sun4i GPADC IIO map registered and runtime PM enabled, causing an incomplete device-probe cleanup without demonstrated memory corruption or host-wide denial of service.

6. Manual review recommendation

NO MANUAL CHECK NEEDED

The issue is a narrow resource-cleanup defect with no demonstrated attacker-controlled accumulation, memory corruption, authorization bypass, or cross-boundary impact.

7. Call-site confidence

Call-site confidence: high

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

Patch: iio: adc: sun4i-gpadc-iio: clean up on thermal zone registration failure
Commit: 1bad19e598cd77884d812fd2f88b05c635b5e7ad
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1bad19e598cd77884d812fd2f88b05c635b5e7ad

Commit description:

If devm_thermal_of_zone_register() fails, probe returns without
unregistering the IIO map array or disabling runtime PM.

Jump to err_map to release them.

Fixes: b0a2428 ("iio: adc: sun4i-gpadc-iio: register in the thermal after registering in pm")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/iio/adc/sun4i-gpadc-iio.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=1bad19e598cd77884d812fd2f88b05c635b5e7ad

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

The original Linux kernel CVE announcement for CVE-2026-98671 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98671

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:L
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
  The Best / paranoid CVSS score: 2.5

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: unknown
  Paranoid ActionableScore: 1

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: LOW
KPANIC detected for this report: NO
Published priority for this report (same as in Subject): LOW

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).