[CVE-2026-99020][LOW] regulator: tps6594-regulator: Fix n_linear_ranges for TPS65224 BUCK2-4

[CVE-2026-99020][LOW] regulator: tps6594-regulator: Fix n_linear_ranges for TPS65224 BUCK2-4

[AL-KERNEL]

CVE: CVE-2026-99020
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: regulator: tps6594-regulator: Fix n_linear_ranges for TPS65224 BUCK2-4
Commit: 1ea151615a82fd94f25e38b2cc7eeac49112508b
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1ea151615a82fd94f25e38b2cc7eeac49112508b
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-99020
Analysis date: Tue, 27 Oct 2026 00:09:21 -0400
ActionableScore: 2
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
An incorrect regulator range count causes a static-array OOB read during affected PMIC registration, potentially yielding failed registration or unstable voltage handling without a demonstrated write or disclosure.

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

The original Linux kernel CVE announcement for CVE-2026-99020 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-99020

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.

======================================================================
AL-KERNEL CLASSIFICATION RESULT
======================================================================

CVE-2026-99020	LOW	https://www.kernelcve.org/list/?q=CVE-2026-99020 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=1 LEGACY=LOW RESULT=DIFF TEMP_DISTANCE_MERGE_SKIP=AEGIS_NO_POSITIVE_SEVERITY_EVIDENCE (final Legacy and Aegis differ; FINAL: LOW, Aegis: MODERATE_KPANIC)	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:H';CWE-125;CWE-805;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.7';DESCR 'The TPS65224 and TPS652G1 BUCK2-4 regulator descriptors report four linear ranges even though the referenced table contains only two entries. Linear range helpers therefore read beyond the static array while checking selectors above 0x45 during normal regulator registration. The demonstrated primitive is an out of bounds read with no supported write or information disclosure path. For the CVSS the PR:H value reflects that reliable attacker controlled triggering generally requires administrative control of kernel or hardware configuration and an affected PMIC. The issue is not network reachable. The expected impact is failed regulator registration or incorrect voltage range handling, while the grounded worst case includes device instability or a system outage if bogus range data influences regulator operation. Automated impact decision path. The original SimpleNet classifier selected LOW. The primary LLM estimated paranoid CVSS 4.7 and the production ActionableScore returned 2 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. Recorded rule transitions were final reconciliation stage LOW to LOW because KP specialist did not establish a qualifying panic and the cross model evidence reconciliation rule was applied. 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. Exact triggered rule markers were KPANIC_UNSUPPORTED_REMOVED and V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED. The independent weaker Aegis shadow evaluated CVSS 2.0 and ActionableScore 1 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was MODERATE_KPANIC. The models disagreed but the aggregation rules retained the production result. The final reported impact is LOW.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 2)	MAYBE	SIMPLEFIX IMPROVEONLY KPANIC_UNSUPPORTED_REMOVED V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED	-	-	checked

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

ActionableScore=2
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=NO
ImportantCandidate=NO
ManualReview=RECOMMENDED
AutoDowngradeAllowed=YES
RequiresHostUID0=UNKNOWN
AuthorizationDecisionBypass=NO
ProtectedResourceImpact=NONE
B4PendingReview=NO
B4PendingConfirmed=NO

1. ActionableScore

* Raw base score: 2.
* Conservative score: 2; no floor or cap applied.
* Raw paranoid score: 2.
* Paranoid score: 2; stronger memory-corruption or crash effects are unsupported.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* +1 weak/indirect corruption concern: `n_linear_ranges=4` makes the linear-range helper read two entries beyond a two-entry static array and interpret adjacent data as voltage-range structures.
* +1 availability concern: bogus range interpretation during normal registration can reject registration or produce unsafe regulator behavior; the supplied evidence identifies device instability or system outage as the grounded worst case.
* No negative privilege or hardware penalty: an affected TPS65224/TPS652G1 PMIC is required, but the evidence does not establish rare physical access or a host-admin-only complete trigger.
* No write, disclosure, UAF, controlled target, authorization bypass, or protected-state modification is shown.
* NEW52/B5-R does not apply: this is a read-only array overrun, with no retry-accumulated index or later consumption of corrupted written state.
* No crash bonus: panic or a reliable kernel fault is not demonstrated.
* No confidentiality or integrity bonus: internally consumed adjacent bytes are not disclosed, and incorrect voltage calculation does not establish unauthorized protected-state corruption.

3. Reachability analysis

The defect executes during ordinary regulator registration on systems containing an affected PMIC. An attacker-invocable interface, selector control, or below-host-admin trigger is not shown. Reliable attacker-directed reprovisioning may require administrative hardware/kernel configuration, but that requirement is not established strongly enough for a privilege penalty or `HostAdminRequired=YES`. This is not namespace-scoped, network-reachable, or race-dependent.

4. Primitive and severity reading

The exact primitive is a bounded-direction but extent-unknown static-array OOB read whose bytes are reinterpreted as additional linear-range entries. It is CLASS_C because the demonstrated consequences are invalid range processing and possible availability impact, not a write, disclosure, lifetime violation, or authorization primitive. Important-grade leverage is absent, so automatic Moderate handling remains permissible.

5. One-sentence report phrase

An incorrect regulator range count causes a static-array OOB read during affected PMIC registration, potentially yielding failed registration or unstable voltage handling without a demonstrated write or disclosure.

6. Manual review advice

MANUAL CHECK RECOMMENDED

Confirm platform-specific consequences of bogus voltage-range data, especially whether any affected board can apply unsafe voltages rather than merely fail registration.

7. Call-site confidence

Call-site confidence: medium

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

Patch: regulator: tps6594-regulator: Fix n_linear_ranges for TPS65224 BUCK2-4
Commit: 1ea151615a82fd94f25e38b2cc7eeac49112508b
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1ea151615a82fd94f25e38b2cc7eeac49112508b

Commit description:

The TPS65224 BUCK2, BUCK3 and BUCK4 descriptors pass 4 as
n_linear_ranges, but tps65224_bucks_2_3_4_ranges[] only has two
entries, covering selectors 0x00-0x45.

The linear range helpers loop over n_linear_ranges entries, so any
lookup of a selector above 0x45 reads past the end of the array and
treats whatever follows it as two more ranges. This happens on the
normal registration path when the core checks the voltage constraints
against every selector. TPS652G1 uses the same descriptors and is
affected too.

Use ARRAY_SIZE() so the count always matches the table.

Fixes: 00c8265 ("regulator: tps6594-regulator: Add TI TPS65224 PMIC regulators")
Cc: stable@vger.kernel.org
Signed-off-by: Ridham Khurana <khurana.ridham222@gmail.com>
Link: https://patch.msgid.link/20260930105333.3522412-1-khurana.ridham222@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/regulator/tps6594-regulator.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=1ea151615a82fd94f25e38b2cc7eeac49112508b

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

The original Linux kernel CVE announcement for CVE-2026-99020 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-99020

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:H/UI:N/S:U/C:N/I:L/A:H
  The Best / paranoid CVSS score: 4.7

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: 2

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).