[CVE-2026-98847][LOW] rtc: spear: initialize IRQ state before requesting alarm IRQ

[CVE-2026-98847][LOW] rtc: spear: initialize IRQ state before requesting alarm IRQ

[AL-KERNEL]

CVE: CVE-2026-98847
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: rtc: spear: initialize IRQ state before requesting alarm IRQ
Commit: c02aa67ea34a826c2cb1aa65d77cf32fafb7eec3
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c02aa67ea34a826c2cb1aa65d77cf32fafb7eec3
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98847
Analysis date: Sat, 24 Oct 2026 04:39:13 -0400
ActionableScore: 0
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
A narrow SPEAr RTC probe race can invoke the alarm handler before its MMIO base and spinlock are initialized, plausibly crashing the kernel.

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

The original Linux kernel CVE announcement for CVE-2026-98847 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98847

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
======================================================================

CVE-2026-98847	LOW	https://www.kernelcve.org/list/?q=CVE-2026-98847 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:L/UI:N/S:U/C:N/I:N/A:H';CWE-362;CWE-665;**CWE-476;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '4.7';DESCR 'A probe time race exists because devm_request_irq enables the alarm interrupt before returning while the IRQ handler depends on config ioaddr and config lock. If an alarm IRQ arrives in this window, spear_rtc_irq may use an uninitialized MMIO base or spinlock and can crash the kernel. For the CVSS the PR:H base value reflects that reliable triggering normally requires privileged control over driver reprobe and RTC alarm state. The paranoid PR:L value covers deployments where a local user can program RTC alarms and device initialization occurs independently. AC:H reflects the narrow interrupt timing window. The demonstrated primitive is an invalid kernel access rather than UAF, OOB access, or arbitrary write, so confidentiality and integrity remain N while availability is H. Automated impact decision path. The original SimpleNet classifier selected MODERATE_KPANIC. The primary LLM estimated paranoid CVSS 4.7 and the production ActionableScore returned 0 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. Recorded rule transitions were CVSS and initial triage stage MODERATE_KPANIC to MODERATE because the CVSS score, vector or bug class threshold rule was applied. ActionableScore thresholds stage MODERATE to LOW because the ActionableScore threshold rule was applied. 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 DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH and DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 and KPANIC_UNSUPPORTED_REMOVED and V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED. The independent weaker Aegis shadow evaluated CVSS 1.9 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.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 0)	MAYBE	OOB LOCK INIT SIMPLEFIX HARDWARE LINUS DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 KPANIC_UNSUPPORTED_REMOVED V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED	-	-	checked

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

ActionableScore=0
PrimitiveClass=CLASS_C
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 base score: 0
* Conservative score: 0
* Raw paranoid score: 0
* Paranoid score: 0
* No floor or cap applied.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* +1 Reliable kernel crash / strong DoS: `devm_request_irq()` enables the IRQ before returning, allowing the handler to access `config->ioaddr` and `config->lock` before initialization. An invalid MMIO access or invalid lock operation can plausibly cause an Oops.
* -1 Hard timing requirement: the interrupt must execute during the narrow probe interval between IRQ enablement and initialization.
* No UAF, OOB access, controlled overwrite, repeated release, or authorization bypass is shown.
* No confidentiality or integrity point: the patch supports invalid initialization-state use and possible crash, not attacker-directed corruption.
* No additional availability point: it would duplicate the same crash.
* NEW52/B5-R does not apply: there is no retry-accumulated heap OOB write or later consumption of corrupted descriptors.
* NEW53/B3-PENDING does not apply: no shared-backing write exists.
* NEW54/B4-PENDING does not apply: no access-control decision is involved.

3. Reachability analysis

The affected driver is probed for SPEAr platform RTC hardware. An alarm IRQ must be pending or arrive during probe. The evidence does not establish who can arrange both reprobe and alarm state: privileged device control is plausible, while independently occurring probe plus user-programmable alarm is only a deployment-dependent possibility. Therefore host-admin requirement and host UID 0 requirement remain unknown. No namespace capability path, prior delegation, or remote trigger is shown.

4. Primitive and severity reading

The primitive is a probe-time initialization race involving active but incompletely initialized driver state. It is neither a lifetime violation nor a confirmed out-of-bounds write. The demonstrated consequence is an invalid MMIO/locking access with plausible kernel crash; useful post-crash leverage is not shown. This is CLASS_C, with no Important-preserving primitive and no reason to prohibit automatic Moderate handling.

5. One-sentence report phrase

A narrow SPEAr RTC probe race can invoke the alarm handler before its MMIO base and spinlock are initialized, plausibly crashing the kernel.

6. Manual review advice

NO MANUAL CHECK NEEDED

The patch shows a hardware-specific, timing-constrained crash path without a material corruption or security-boundary primitive.

7. Call-site confidence

Call-site confidence: medium

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

Patch: rtc: spear: initialize IRQ state before requesting alarm IRQ
Commit: c02aa67ea34a826c2cb1aa65d77cf32fafb7eec3
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c02aa67ea34a826c2cb1aa65d77cf32fafb7eec3

Commit description:

devm_request_irq() enables the interrupt before it returns, so the handler
may run while probe is still initializing the device. Initialize the MMIO
address and spinlock before requesting the alarm IRQ.

Fixes: 0942a71 ("rtc: add support for spear rtc")
Cc: stable@vger.kernel.org
Assisted-by: Codex:GPT-5
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Link: https://patch.msgid.link/20260902080318.3498434-1-runyu.xiao@seu.edu.cn
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/rtc/rtc-spear.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=c02aa67ea34a826c2cb1aa65d77cf32fafb7eec3

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

The original Linux kernel CVE announcement for CVE-2026-98847 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98847

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:N/I:N/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: 0

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).