[CVE-2026-98263][LOW] ASoC: codecs: rt712-sdca-dmic: fix uninitialized stream_config->type

[CVE-2026-98263][LOW] ASoC: codecs: rt712-sdca-dmic: fix uninitialized stream_config->type

[AL-KERNEL]

CVE: CVE-2026-98263
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: ASoC: codecs: rt712-sdca-dmic: fix uninitialized stream_config->type
Commit: 6507055733a9d397289277408b52daf422f8a814
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6507055733a9d397289277408b52daf422f8a814
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98263
Analysis date: Sat, 10 Oct 2026 15:28:27 -0400
ActionableScore: 1
ActionableScore lower bound: 0
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-2026-98263 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98263

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-2026-98263	LOW	https://www.kernelcve.org/list/?q=CVE-2026-98263 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT LOW AEGIS_AS=1 LEGACY=LOW RESULT=SAME (legacy and Aegis reconciliation agree; DECISION: both LOW)	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L';*CWE-457;CWE-908;CWE-665;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '3.3';DESCR 'An uninitialized sdw_stream_config structure can pass a garbage type value from rt712_sdca_dmic_hw_params into the SoundWire stream state. The expected default is SDW_STREAM_PCM, but an arbitrary stack value may cause the stream to be classified or configured incorrectly and can prevent the affected audio stream from operating. For the CVSS the PR:L value is used because a local process must have permission to open and configure the corresponding ALSA PCM device. The issue is not network reachable. The demonstrated impact is limited availability loss for the audio stream or device, with no supported UAF, out of bounds access, information disclosure, kernel crash, or privilege escalation primitive.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1)	MAYBE	SIMPLEFIX HARDWARE 	-	-	checked

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

ActionableScore=1
ActionableScoreLower=0
PrimitiveClass=NONE
RealUAF=NO
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=UNKNOWN
ImportantCandidate=NO
ManualReview=NO
AutoDowngradeAllowed=YES
RequiresHostUID0=UNKNOWN
AuthorizationDecisionBypass=NO
ProtectedResourceImpact=NONE
B4PendingReview=NO
B4PendingConfirmed=NO

1. ActionableScore

* Raw conservative score: 0
* Conservative score: 0
* Raw paranoid score: 1
* Paranoid score: 1
* No floor or cap applied.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

Conservative signals:

* +0 Uninitialized ordinary value. `stream_config.type` contains stack garbage and is copied into `stream->type`, but no OOB access, UAF, disclosure, write primitive, or kernel crash is established.
* +0 Device-local effect. The supplied evidence does not demonstrate that the invalid type causes a reliable audio failure.

Paranoid signals:

* +1 Availability impact. Consumption of an invalid SoundWire stream type can plausibly prevent configuration or operation of the affected audio stream or codec. This remains device-local and does not establish host-wide DoS.

Not awarded:

* B5-R is not established. There is no heap OOB write, retry-accumulated offset, or later consumption of corrupted heap descriptors.
* B3-PENDING is not established. No shared-backing or file-backed write occurs.
* B4-PENDING is not established. No authorization guard or DENY-to-ALLOW transition exists.
* No local-unprivileged bonus because permission to access the relevant ALSA PCM device is deployment-dependent.
* No memory-corruption, confidentiality, integrity, LPE, remote-reachability, or strong-DoS points.
* No hardware rarity penalty because the evidence establishes hardware specificity but not a qualifying rare-hardware prerequisite.

3. Reachability analysis

The path is reached through `rt712_sdca_dmic_hw_params()` while configuring an ALSA PCM stream on hardware using the RT712 SDCA microphone codec. A local process with access to the corresponding PCM device may invoke this operation, but the supplied evidence does not establish whether an ordinary user, an audio service, or an administrator owns the complete trigger in affected deployments.

No namespace-scoped capability path, prior privileged setup beyond normal device and driver availability, network trigger, race, or retry sequence is shown. Host-admin-equivalent privilege is neither required nor ruled out by the available evidence, so `HostAdminRequired=UNKNOWN`.

4. Primitive and severity interpretation

The exact defect is use of an uninitialized stack field followed by semantic consumption as a SoundWire stream type. This is an invalid ordinary enum value, not an OOB stack read that is disclosed and not a demonstrated type confusion involving incompatible kernel object layouts.

There is no stale storage, UAF, repeated release, refcount mutation, authorization bypass, shared-page ownership violation, or active-state retirement failure. The demonstrated mechanism supports incorrect stream configuration. Device-local audio failure is a defensible paranoid consequence, while kernel panic, memory corruption, and privilege escalation are unsupported.

`PrimitiveClass=NONE` is appropriate because no meaningful corruption, lifetime, ownership, or security-boundary primitive is established. Automatic downgrade is allowed because the issue is a constrained device-configuration defect with no unresolved Important-grade primitive.

5. One-sentence report phrase

An uninitialized SoundWire stream type can cause incorrect RT712 audio stream configuration and possible device-local audio failure, but no kernel memory corruption, authorization bypass, host-wide crash, or privilege-escalation primitive is established.

6. Manual review recommendation

NO MANUAL CHECK NEEDED

The patch corrects an uninitialized ordinary configuration field, and the supplied call-path evidence does not establish any Important-preserving primitive.

7. Call-site confidence

Call-site confidence: medium

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

Patch: ASoC: codecs: rt712-sdca-dmic: fix uninitialized stream_config->type
Commit: 6507055733a9d397289277408b52daf422f8a814
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6507055733a9d397289277408b52daf422f8a814

Commit description:

stream_config is not initialized before being passed to
sdw_stream_add_slave().  The type field may contain garbage and is
later copied to stream->type by sdw_config_stream().

Zero-initialize stream_config so type defaults to SDW_STREAM_PCM.

While at it, use snd_sdw_params_to_config() helper instead of
open-coding the same logic.

Fixes: 63a5112 ("ASoC: rt712-sdca: Add RT712 SDCA driver for Mic topology")
Cc: stable@vger.kernel.org
Signed-off-by: Jiangshan Yi <yijiangshan@kylinos.cn>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.dev>
Link: https://patch.msgid.link/20260914104712.379574-1-yijiangshan@kylinos.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  sound/soc/codecs/rt712-sdca-dmic.c
  sound/core.h
  sound/pcm.h
  sound/pcm_params.h
  sound/sdw.h
  sound/tlv.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=6507055733a9d397289277408b52daf422f8a814

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

The original Linux kernel CVE announcement for CVE-2026-98263 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98263

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:L/PR:L/UI:N/S:U/C:N/I:N/A:L
  The Best / paranoid CVSS score: 3.3

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: 0
  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).