[CVE-2026-80911][MODERATE 7.0] ASoC: SOF: sof-audio: Fix error path in sof_widget_setup_unlocked()

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

CVE: CVE-2026-80911
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: ASoC: SOF: sof-audio: Fix error path in sof_widget_setup_unlocked()
Commit: b270ed327380428581bbcbd85707f62e942428d7
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b270ed327380428581bbcbd85707f62e942428d7
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80911
Analysis date: Fri, 04 Sep 2026 16:17:19 -0400
ActionableScore: 5
ActionableScore lower bound: 2
Actionable bucket: Actionable Moderate at minimum
Manual review required: YES

Summary:
ASoC/SOF widget setup can double decrement widget use_count and call core_put twice on an error path, causing corrupted lifetime accounting and possible local audio or DSP subsystem denial of service.

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

The original Linux kernel CVE announcement for CVE-2026-80911 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80911

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 7.0
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-2026-80911	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-80911 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:L/A:H';CWE-911;*CWE-672;*CWE-664;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.8';DESCR 'ASoC/SOF widget setup has an error path where sof_widget_free_unlocked() may be called and then execution can fall through into additional cleanup, causing a second use_count decrement and a second core_put(). This is a reference or lifetime accounting bug in kernel audio topology setup and may leave widget or DSP core state inconsistent after a setup failure. For the CVSS the PR:L is used for the paranoid interpretation because a local user or delegated audio service may be able to influence audio topology setup or recovery paths in some deployments, even though typical direct control is administrative. The issue is not network reachable and requires local interaction with the audio driver stack or a failing topology setup path. Impact is at least local denial of service or audio subsystem failure. In the worst still defensible case it may allow limited confidentiality or integrity impact through corrupted lifetime accounting and should be reviewed manually.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate at minimum (with actual score 4)	YES	INIT SIMPLEFIX ERRORPATH HARDWARE  INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_FALSEPOSCHECKOFKP	YES	NO	checked

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

ActionableScore=5
ActionableScoreLower=2

## 1. ActionableScore

* Conservative score: 2
* Paranoid score: 5
* Final recommended bucket: **Actionable Moderate at minimum**::

## 2. Signal breakdown

Conservative signals:

* Weak/indirect corruption candidate: +1. The bug is a double decrement of `use_count` and double `core_put()`, but the patch does not show attacker controlled reclaim, arbitrary write, type confusion, or callback control.
* Real lifetime corruption: +1. The affected path corrupts lifetime/accounting state for SOF widgets and DSP core usage.
* Privileged kernel/device-management lifetime path: +1. The bug is inside kernel audio/DSP topology setup and core management.
* Availability impact realistic: +1. A failed setup path can leave audio/DSP state inconsistent and may cause local subsystem failure.
* Requires admin/root or privileged service in typical deployments: -2. Direct topology setup and driver initialization are normally controlled by root, firmware loading, or system audio services.

Paranoid additions/changes:

* Local unprivileged or delegated-service trigger: +1. In some deployments, a local user or audio service may indirectly reach widget setup or recovery paths through normal audio use.
* Weak LPE concern: +1. Double put/use-count corruption is a lifetime bug and deserves manual review, even though no concrete LPE primitive is demonstrated.
* Special failure condition required: -1. Triggering depends on `tplg_ops->dai_config` or `widget_kcontrol_setup` failing at the right setup stage.

## 3. Reachability analysis

The bug is local and not network reachable. Typical direct control over SOF topology loading, firmware, and driver setup is administrative, so the conservative model treats this as privileged. A less strict model is plausible because local audio workloads or reduced-privilege audio services may trigger widget setup, teardown, or recovery paths on systems using SOF audio. The path is hardware and configuration dependent, mostly relevant to systems using Intel SOF audio, but this is not obscure enough to fully dismiss.

Call-site confidence: medium. The patch shows the affected cleanup labels and the double cleanup behavior, but the full caller graph and exact user-triggerable setup paths are not included.

## 4. Severity interpretation

This is not an Important-class candidate based on the supplied patch alone. It behaves like an Actionable Moderate lifetime/accounting bug because it involves double cleanup of kernel-managed widget/core state, but lacks evidence of controlled UAF reclaim, arbitrary write, callback hijack, or reliable privilege escalation. The realistic impact is local DoS or audio/DSP subsystem instability. The paranoid concern is limited C/I impact from corrupted lifetime accounting, not proven full kernel compromise.

## 5. One-sentence report phrase

ASoC/SOF widget setup can double decrement widget use_count and call core_put twice on an error path, causing corrupted lifetime accounting and possible local audio or DSP subsystem denial of service.

## 6. Manual review recommendation

MANUAL CHECK REQUIRED. YES REQUIRES MANUAL CHECK.

Reason: this is a kernel lifetime/accounting bug involving double cleanup, and such bugs can hide stronger impact than the visible error-path fix, even though the patch does not prove a strong exploitation primitive.

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

Patch: ASoC: SOF: sof-audio: Fix error path in sof_widget_setup_unlocked()
Commit: b270ed327380428581bbcbd85707f62e942428d7
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b270ed327380428581bbcbd85707f62e942428d7

Commit description:

If either tplg_ops->dai_config or widget_kcontrol_setup fail during widget
setup we would double decrement the use_count of the widget because the
sof_widget_free_unlocked() would be called twice, similarly the core_put
would be invoked twice as well.

Since the use_count and core_put() is handled within the widget_free
function we need to return without falling through the pipe_widget_free
label.

The fixes tag is picked to the last change around this part of the code
which is adequately old enough for backporting purposes.

Link: thesofproject/sof#10826
Fixes: 31ed8da ("ASoC: SOF: sof-audio: Modify logic for enabling/disabling topology cores")
Cc: stable@vger.kernel.org
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://patch.msgid.link/20260730085914.27546-1-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  sound/soc/sof/sof-audio.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=b270ed327380428581bbcbd85707f62e942428d7

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

The original Linux kernel CVE announcement for CVE-2026-80911 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80911

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:L
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H
  The Best / paranoid CVSS score: 5.8

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: 2
  Paranoid ActionableScore: 5

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 7.0

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).