[CVE-2026-97978][MODERATE REGULAR] eth: ice: don't dereference pointers from TP_printk() [ Upstream

[AL-KERNEL <alkernel@kernelcve.org>]

CVE: CVE-2026-97978
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: eth: ice: don't dereference pointers from TP_printk() [ Upstream
Commit: ae230874e3ba27e975a9bb21a6ffd05d6a2ea318
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ae230874e3ba27e975a9bb21a6ffd05d6a2ea318
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97978
Analysis date: Sat, 26 Sep 2026 14:32:07 -0400
ActionableScore: 4
ActionableScore lower bound: unknown
Actionable bucket: Borderline / manual review recommended
Manual review required: YES

Summary:
No one-sentence report phrase was found.

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

The original Linux kernel CVE announcement for CVE-2026-97978 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97978

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 REGULAR
Manual review required: YES

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

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

CVE-2026-97978	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-97978 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:H/I:N/A:H';*CWE-416;CWE-825;*CWE-200;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:L';BEST CVSS score: '6.3';DESCR 'The ice DIM trace events stored q_vector and dim pointers in the trace record and dereferenced them later from TP_printk(). Trace output can be generated long after event recording, so the ring or DIM object may already be freed or reused. This creates a potential use-after-free read that can expose stale kernel data or cause an invalid memory access, an Oops, and potentially a system denial of service when panic_on_oops is enabled. No write primitive is visible, so direct integrity impact or privilege escalation is not supported by this patch. For the CVSS the PR:L value in the paranoid score reflects deployments where tracefs access or control of these trace events is delegated to a non root service account. The normal configuration generally requires administrative tracing privileges and corresponds to PR:H. The issue is not directly network reachable. Network traffic may generate DIM activity, but an attacker still needs local tracing access and a suitable object lifetime transition. AC:H reflects the timing and configuration conditions required to observe a stale pointer dereference.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 4)  SKIP CVE-2026-97978 UNKNOWN SKIP No affected files built, so skip this CVE NO  - - unknown 	MAYBE	REMOTE TRACE NETWORK TEST  DECREASED_TO_MODERATEREG_BASED_ON_FALSEPOSCHECKOFKP	-	-	checked

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

ActionableScore=4
PrimitiveClass=CLASS_B
RealUAF=YES
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=NO
ImportantCandidate=NO
ManualReview=RECOMMENDED
AutoDowngradeAllowed=YES

1. ActionableScore

* Raw conservative score: 3
* Conservative score: 4
* Raw paranoid score: 4
* Paranoid score: 4
* Applied conservative floor: 3 -> 4 under REAL UAF FLOOR 4. A stale reference is actually consumed, the objects are active structured objects rather than fixed stale buffers, and host-admin-equivalent privilege is not positively established.
* No paranoid floor or cap changed the raw score.
* Final recommended bucket: **Borderline / manual review recommended**::

2. Signal breakdown

Conservative signals:

* +2 Real UAF / lifetime violation. The trace record retains pointers to `ice_q_vector` and `dim`, while `TP_printk()` dereferences them after their referenced objects may have been freed.
* +1 Confidentiality plausible. The stale reads are formatted into trace output, providing a concrete user-visible path for scalar bytes read from freed or reused storage.
* +0 Reliable kernel crash. An invalid dereference can plausibly fault, but the supplied evidence directly demonstrates the tracing warning rather than an actual Oops or panic.
* Raw conservative score: 2 + 1 = 3.

Paranoid signals:

* +2 Real UAF / lifetime violation.
* +1 Confidentiality plausible through trace output.
* +1 Strong DoS. If the retained pointer becomes unmapped or otherwise invalid, delayed formatting can produce an Oops and may panic a system configured with `panic_on_oops`.
* Raw paranoid score: 2 + 1 + 1 = 4.

Not awarded:

* No strong or weak LPE point. The stale path performs fixed-width reads only.
* No structured stale-object leverage. Only `q_index` and small DIM scalar fields are consumed. No pointers, callbacks, ownership fields, lengths used for memory access, or refcounts are consumed.
* No controlled reclaim, object replacement, arbitrary write, directed read, callback control, or credential effect is demonstrated.
* No separate Availability point. The possible Oops or panic is the same consequence already represented by the paranoid DoS point.
* No remote-reachability point. Network traffic may generate DIM events, but it cannot independently enable or read tracefs or force the complete lifetime sequence.
* No race penalty. The delayed formatting creates a lifetime window, but the supplied evidence does not establish a narrow or difficult one-shot race.
* No hardware penalty. An Intel ICE device is required, but the evidence does not establish rare or physical-attacker-only hardware.
* No repeated release/refcount signal. There is no first lifetime-ending release followed by a second put, free, or refcount mutation through the same reference.
* FLOOR 5 was not applied because the stale operation is a shallow read-only trace formatter with no meaningful active-object processing or lifetime mutation.

3. Reachability analysis

The vulnerable trace events arise from ICE RX or TX DIM activity. Network traffic can influence event generation, but traffic alone does not reach the delayed pointer dereference as an attacker-visible security operation. The tracepoint must be enabled, retained records must be formatted or read later, and the associated ring, queue vector, or DIM instance must lose its lifetime before formatting.

Tracefs access is normally host-global and administratively restricted, but the supplied evidence does not prove that host-admin-equivalent privilege is mandatory in every deployment because tracing access can be delegated. Therefore `HostAdminRequired=UNKNOWN`. This is not a namespace-scoped capability path. Creating a user or network namespace does not provide control of host tracefs or the physical ICE device, so `NamespaceScopedPrivilege=NO`.

The complete trigger may also involve device teardown, reset, queue reconfiguration, or another lifetime transition. The supplied patch does not establish that an ordinary user can control that transition. It also does not establish a narrow, externally uncontrollable race, so no timing penalty is applied.

4. Primitive and severity interpretation

The exact primitive is a delayed stale-pointer read from potentially freed or reused `ice_q_vector`, ring, or `dim` storage. This is a real lifetime violation and therefore CLASS_B rather than a warning-only CLASS_C issue.

The affected objects are active structured kernel objects, but the stale path uses only a small fixed set of scalar fields for textual trace formatting. It does not follow stale pointers beyond the shown queue-ring dereference, dispatch through operations, modify refcounts, write through the stale object, or perform resource decisions based on reclaimed state.

The demonstrated security-relevant consequence is possible disclosure of stale scalar data through trace output. A kernel fault is technically plausible if the stale address is invalid, but no crash is shown in the supplied evidence. Privilege escalation, arbitrary kernel access, and controlled object substitution remain speculative and are not scored.

`ImportantCandidate=NO` because no meaningful exploitation leverage beyond shallow stale reads, limited trace disclosure, and possible faulting is established. `AutoDowngradeAllowed=YES` because this is a constrained read-only CLASS_B case without repeated lifetime mutation, controlled reclaim, write primitive, callback influence, or security-boundary bypass. Operationally it is a borderline Moderate issue warranting confirmation rather than an Important-class candidate.

5. One-sentence report phrase

The ICE DIM tracepoints can dereference stale q_vector or dim pointers during delayed trace formatting, potentially exposing reused kernel data or causing an invalid memory access, but no write or privilege-escalation primitive is established.

6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Confirm whether affected kernels permit delegated access to these ICE trace events and whether queue teardown or reset can reliably occur while unread records remain, as those facts determine the practical disclosure and crash exposure.

7. Call-site confidence

Call-site confidence: medium

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

Patch: eth: ice: don't dereference pointers from TP_printk() [ Upstream
Commit: ae230874e3ba27e975a9bb21a6ffd05d6a2ea318
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ae230874e3ba27e975a9bb21a6ffd05d6a2ea318

Changed files:
  kernel/trace/trace_events.c
  drivers/net/ethernet/intel/ice/ice_trace.h

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=ae230874e3ba27e975a9bb21a6ffd05d6a2ea318

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

The original Linux kernel CVE announcement for CVE-2026-97978 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97978

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:L/I:N/A:L
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:H
  The Best / paranoid CVSS score: 6.3

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: 4

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 REGULAR

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).