[CVE-2026-97899][LOW] drm/i915: Fix memory leak in query_perf_config_list()

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

CVE: CVE-2026-97899
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: drm/i915: Fix memory leak in query_perf_config_list()
Commit: d004303557924077a327d71c80f5863b1b9ff1d7
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d004303557924077a327d71c80f5863b1b9ff1d7
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97899
Analysis date: Sat, 26 Sep 2026 16:10:39 -0400
ActionableScore: 1
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
No one-sentence report phrase was found.

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

The original Linux kernel CVE announcement for CVE-2026-97899 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97899

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-2026-97899	LOW	https://www.kernelcve.org/list/?q=CVE-2026-97899 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:N/I:N/A:H';*CWE-401;**CWE-400;*CWE-772;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.7';DESCR 'A memory leak in the i915 query_perf_config_list path occurs when krealloc fails and the previously allocated oa_config_ids buffer is not released before returning ENOMEM. A local process with access to the relevant DRM i915 interface may repeatedly trigger the failure path under memory pressure and gradually consume kernel memory. For the CVSS the PR:L value is used because a local process with DRM device access is required. The issue is not network reachable. Impact is primarily denial of service through resource exhaustion. No memory corruption information disclosure integrity impact or privilege escalation primitive is indicated by the affected code path.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1)	YES	SIMPLEFIX LEAK HARDWARE 	YES	NO	checked

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

ActionableScore=1
PrimitiveClass=NONE
RealUAF=NO
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=UNKNOWN
ImportantCandidate=NO
ManualReview=NO
AutoDowngradeAllowed=YES

1. ActionableScore

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

2. Signal breakdown

* +1 Concrete persistent kernel resource leak. When `krealloc()` fails, the original `oa_config_ids` allocation is lost because the function returns `-ENOMEM` without freeing it. The patch directly adds `kfree(oa_config_ids)` on that path.
* +0 Reliable kernel crash or strong DoS. No crash, panic, lockup, immediate allocation exhaustion, or system-wide resource failure is established.
* +0 Repeated triggering. Repeated invocation is plausible for an ioctl query interface, but the supplied patch does not establish a practical rate, retained allocation size, or a realistic path to host-wide memory exhaustion.
* +0 Local unprivileged trigger. The patch alone does not establish that the complete relevant i915 DRM query operation is accessible to an ordinary unprivileged user in the evaluated deployment.
* +0 Strong or weak exploitation leverage. This is a missing cleanup on allocation failure, not a UAF, double free, OOB access, ownership violation, or active-object corruption primitive.
* +0 Confidentiality and integrity impact. There is no disclosure, unauthorized modification, controlled overwrite, or security-boundary bypass.
* No negative privilege, hardware, race, or niche-subsystem penalties were applied because no such restriction is positively established by the supplied evidence.

3. Reachability analysis

The affected path is in the Intel i915 DRM query implementation and is reached when querying OA performance configuration identifiers. The leak requires `krealloc()` failure after the original `oa_config_ids` allocation exists.

The trigger is local and requires access to the relevant DRM i915 query interface. The supplied patch does not establish whether the complete operation is permitted for an ordinary render-node user, a DRM master, a compositor, a delegated graphics service, or only a host administrator in the evaluated product. Therefore `HostAdminRequired=UNKNOWN`.

No network path, namespace-specific capability path, prior host provisioning requirement, special boot option, or special physical hardware requirement is established beyond use of an affected Intel i915 GPU driver. This is not a race.

4. Primitive and severity interpretation

The exact defect is a concrete memory/resource leak on an error path. `krealloc()` returns `NULL` on failure while preserving the original allocation, but the original `oa_config_ids` pointer was not released before returning `-ENOMEM`.

This is not active structured-object lifetime corruption. There is no stale pointer dereference, no second lifetime mutation, no UAF, no refcount misuse, no controlled reclaim, no arbitrary write, and no authorization primitive. The relevant primitive class is therefore `NONE`.

The demonstrated consequence is incremental kernel-memory retention on repeated allocation-failure paths. Host-wide denial of service through sustained memory exhaustion is theoretically possible but is not established by the patch because the required allocation pressure, repeatability, retained allocation size, and practical accumulation rate are unknown.

`ImportantCandidate=NO` because no meaningful corruption, security-boundary, ownership, or exploitation primitive remains unresolved. `AutoDowngradeAllowed=YES` because this is a constrained resource-leak fix with no demonstrated path beyond possible resource exhaustion.

5. One-sentence report phrase

A memory leak in the i915 performance configuration query path leaves the original oa_config_ids allocation unreleased when krealloc fails, potentially causing incremental local resource consumption under repeated memory-pressure conditions.

6. Manual review recommendation

NO MANUAL CHECK NEEDED

The patch establishes a bounded error-path memory leak only, without memory corruption, lifetime misuse, authorization bypass, remote reachability, or a demonstrated practical host-wide exhaustion path.

7. Call-site confidence

Call-site confidence: medium

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

Patch: drm/i915: Fix memory leak in query_perf_config_list()
Commit: d004303557924077a327d71c80f5863b1b9ff1d7
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d004303557924077a327d71c80f5863b1b9ff1d7

Commit description:

When krealloc() fails, free the original oa_config_ids before returning
to avoid a memory leak.

Fixes: 4f6ccc7 ("drm/i915: add support for perf configuration queries")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patch.msgid.link/20260823205028.178597-2-thorsten.blum@linux.dev
(cherry picked from commit 9977e9d84f46d4f12ad35fbbc0ec4638554bce87)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/gpu/drm/i915/i915_query.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=d004303557924077a327d71c80f5863b1b9ff1d7

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

The original Linux kernel CVE announcement for CVE-2026-97899 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97899

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:L
  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: 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).