[CVE-2026-97917][MODERATE REGULAR] accel/ivpu: Validate full buffer range in ivpu_to_cpu_addr

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

CVE: CVE-2026-97917
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: accel/ivpu: Validate full buffer range in ivpu_to_cpu_addr
Commit: 5419be345f32222750e006b85b7f9bae1a285c8e
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5419be345f32222750e006b85b7f9bae1a285c8e
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97917
Analysis date: Fri, 25 Sep 2026 09:36:20 -0400
ActionableScore: 2
ActionableScore lower bound: 1
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
An incomplete IVPU IPC buffer range check can permit a VPU supplied address near the end of a buffer object to cause an out-of-bounds kernel read, potentially resulting in a local kernel fault or denial of service, but no controlled write, disclosure, or privilege-escalation primitive is established.

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ABOUT THIS REPORT
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The original Linux kernel CVE announcement for CVE-2026-97917 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97917

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: 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-2026-97917	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-97917 CHECK WITH IMPACT FROM ORIG NN 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:L/I:N/A:H';CWE-125;*CWE-20;CWE-119;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.3';DESCR 'An incomplete range check in the Intel ivpu IPC path can accept a VPU address near the end of a buffer object even when reading the full IPC header or JSM message crosses the buffer boundary. A local actor who can access the ivpu accelerator and influence malformed VPU IPC state may cause an out of bounds kernel read in the IRQ processing path, potentially resulting in a kernel fault or denial of service. For the CVSS the PR:L is used because a local user context with access to the accelerator is required. The issue is not directly network reachable. The patch context does not demonstrate an out of bounds write or a reliable information disclosure primitive. Impact is at least local denial of service. The paranoid score includes limited confidentiality impact because the bug class is an out of bounds read and should be reviewed manually.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 2)	YES	OOB SIMPLEFIX HARDWARE  DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH	YES	NO	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=2
ActionableScoreLower=1
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=UNKNOWN
ImportantCandidate=NO
ManualReview=RECOMMENDED
AutoDowngradeAllowed=YES

## 1. ActionableScore

* Raw conservative score: 1
* Conservative score: 1
* Raw paranoid score: 2
* Paranoid score: 2
* Final recommended bucket: **Ordinary Moderate**::

No floor or cap was applied.

## 2. Signal breakdown

Conservative signals:

* +1 Weak invalid memory-access concern. The old helper validated only the start address against the buffer object range. A VPU-provided address near the end of the RX buffer object could pass validation even though reading a complete `ivpu_ipc_hdr` or `vpu_jsm_msg` crosses the BO boundary.

Paranoid-only signal:

* +1 Plausible kernel fault or local DoS. The invalid pointer is consumed in the VPU IPC IRQ processing path. Reading a structure beyond the mapped BO can plausibly cause a kernel fault depending on adjacent mapping and allocation layout.

Important non-awarded signals:

* Controlled reclaim is not demonstrated.
* Arbitrary or directed kernel write is not demonstrated.
* The patch establishes an out-of-bounds read condition, not an out-of-bounds write.
* Confidentiality impact is not awarded. No bytes are shown copied back to userspace, network, device-visible output, logs, or another disclosure sink.
* Integrity impact is not awarded. The shown code only converts addresses and subsequently reads IPC header or message data.
* Remote reachability is not established. The malformed address is delivered through VPU firmware IPC, not directly by network traffic.
* Local unprivileged reachability is not awarded. The supplied context does not establish that an ordinary user can induce attacker-controlled malformed VPU IPC addresses.
* Firmware-mediated external influence is not awarded because attacker influence over VPU firmware IPC state is not established.
* Reliable kernel crash is not awarded in the conservative score. The supplied evidence supports a possible fault, but not an observed reliable panic.
* No UAF, double free, refcount misuse, active-object lifetime violation, or repeated release operation is established.

## 3. Reachability analysis

The vulnerable conversion is used by the Intel IVPU driver while processing IPC messages from the VPU device or firmware. The relevant malformed values are `vpu_addr` and `ipc_hdr->data_addr`, which are consumed in `ivpu_ipc_irq_handler()`.

A local process may access IVPU through the accelerator or DRM interface, but the supplied patch does not establish that such a process can cause the VPU firmware to emit an arbitrary malformed IPC address. The complete trigger may require a firmware defect, unexpected device state, or a separate attacker-controlled firmware or workload path.

Host-admin-equivalent privilege is not positively established, so `HostAdminRequired=UNKNOWN`. Below-host-admin reachability is also not positively established for the complete path, so it cannot be classified as `HostAdminRequired=NO`.

No namespace-specific capability checks or complete namespace-scoped trigger sequence are supplied. `NamespaceScopedPrivilege=UNKNOWN`.

The issue requires Intel VPU hardware and the IVPU driver, but no rare-hardware penalty is applied because the patch does not establish that the hardware requirement is physical-only, unusually rare, or otherwise a concrete reducing condition.

## 4. Primitive and severity interpretation

The exact primitive is an incomplete bounds check resulting in a possible out-of-bounds kernel read. The original `ivpu_to_cpu_addr()` accepted an address if its starting byte was inside a buffer object. It did not ensure that the complete object subsequently read through that pointer remained inside the BO.

The fixed code validates both `size <= bo_size` and `offset <= bo_size - size`, preventing a structure read that crosses the BO boundary. The subtraction-based check also avoids an overflow-prone `vpu_addr + size` end calculation.

This is not a UAF, not an active-object lifetime violation, and not a repeated release or refcount mutation. It is therefore `PrimitiveClass=CLASS_C`, because the demonstrated effect is invalid-state handling and a potentially faulting invalid read without an independently useful corruption, disclosure, or authorization primitive.

A kernel fault or local DoS is technically plausible if the out-of-range access reaches unmapped or invalid memory. However, the patch does not demonstrate a controlled disclosure path, memory write, controlled target selection beyond the BO boundary, privilege escalation, or attacker-controlled replacement state.

`ImportantCandidate=NO` because the supplied evidence does not establish meaningful exploitation leverage beyond a potentially faulting out-of-bounds read. `AutoDowngradeAllowed=YES` because no unresolved Class A or strong Class B lifetime, ownership, authorization, write, or boundary-bypass primitive remains.

## 5. One-sentence report phrase

An incomplete IVPU IPC buffer range check can permit a VPU supplied address near the end of a buffer object to cause an out-of-bounds kernel read, potentially resulting in a local kernel fault or denial of service, but no controlled write, disclosure, or privilege-escalation primitive is established.

## 6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Review whether unprivileged users of the IVPU interface can influence VPU firmware IPC addresses or message contents, and whether an out-of-range read can reach a mapped adjacent allocation, disclose data, or reliably crash the host kernel.

## 7. Call-site confidence

Call-site confidence: medium

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

Patch: accel/ivpu: Validate full buffer range in ivpu_to_cpu_addr
Commit: 5419be345f32222750e006b85b7f9bae1a285c8e
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5419be345f32222750e006b85b7f9bae1a285c8e

Commit description:

Add a size parameter to ivpu_to_cpu_addr() and validate that the
whole [vpu_addr, vpu_addr + size) range stays within the BO.

Cc: stable@vger.kernel.org
Fixes: 647371a ("accel/ivpu: Add GEM buffer object management")
Signed-off-by: Magdalena Schulfer <magdalena.schulfer@intel.com>
Signed-off-by: Dawid Osuchowski <dawid.osuchowski@linux.intel.com>
Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com>
Signed-off-by: Karol Wachowski <karol.wachowski@linux.intel.com>
Link: https://patch.msgid.link/20260901125749.404338-2-dawid.osuchowski@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/accel/ivpu/ivpu_gem.h
  drivers/accel/ivpu/ivpu_ipc.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=5419be345f32222750e006b85b7f9bae1a285c8e

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

The original Linux kernel CVE announcement for CVE-2026-97917 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97917

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:L/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:N/A:H
  The Best / paranoid CVSS score: 5.3

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: 1
  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: 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).