[CVE-2026-72263][LOW] ASoC: SOF: topology: fix memory leak in snd_sof_load_topology

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

CVE: CVE-2026-72263
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: ASoC: SOF: topology: fix memory leak in snd_sof_load_topology
Commit: 6ed7787c43ecf4ae27a3e700cab53a1ed646c7f8
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6ed7787c43ecf4ae27a3e700cab53a1ed646c7f8
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72263
Analysis date: Sat, 15 Aug 2026 03:49:02 -0400
ActionableScore: 0
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate / Low-like
Manual review required: NO

Summary:
No one-sentence report phrase was found.

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

The original Linux kernel CVE announcement for CVE-2026-72263 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72263

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.

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

CVE-2026-72263	LOW	CHECK WITH IMPACT FROM ORIG NN LOW	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H';*CWE-401;*CWE-772;**CWE-400;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.4';DESCR 'A memory leak in the ASoC SOF topology loading path occurs because tplg_files is allocated before the dummy topology error check and is not freed before returning EINVAL. Repeated failed topology load attempts with a dummy topology filename can leak kernel memory and may eventually contribute to resource exhaustion. For the CVSS the PR:H is used because reliable triggering normally requires administrative control over SOF topology loading, firmware configuration, or driver reprobe on the victim system. The issue is not network reachable and does not provide a known memory corruption primitive. Impact is denial of service only through memory consumption.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 0)	YES	SIMPLEFIX LEAK HARDWARE 	YES	NO	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=0

1. ActionableScore
* Conservative score: 0
* Paranoid score: 0
* Final recommended bucket: **Ordinary Moderate / Low-like**

2. Signal breakdown
* Memory leak / resource leak: informational classification only. The patch frees `tplg_files` on an error path.
* Availability impact realistic: +1 only in a sustained repeated-trigger scenario, but this is offset by privilege and reachability limits.
* Requires admin/root/CAP-like control in typical deployments: -2. Reliable triggering normally requires control over SOF topology loading, firmware/topology configuration, or driver reprobe.
* Rare AND difficult-to-reach subsystem/configuration: -1. ASoC SOF topology loading is hardware and configuration dependent, not a broad default attack surface.
* No memory corruption primitive: no UAF, OOB access, double free, arbitrary write, refcount abuse, or stale callback is shown.
* No confidentiality or integrity signal: the leak is kernel memory allocation loss, not information disclosure.

3. Reachability analysis
A normal remote attacker cannot trigger this path. A local unprivileged user is also unlikely to trigger it in typical deployments because SOF topology selection and driver loading are controlled by the system or administrator. Containers and namespaces generally do not lower the privilege requirement unless the environment explicitly delegates hardware or driver management, which is uncommon. The bug requires repeated failed topology load attempts with a `dummy` topology filename and `tplg_cnt == 0`.

Call-site confidence: high. The patch shows the direct allocation cleanup error path and the consequence is clear.

4. Severity interpretation
This behaves like an ordinary Low-like or low Moderate resource leak. The theoretical worst case is memory exhaustion after repeated privileged attempts, but there is no realistic evidence of privilege escalation, data corruption, or security-boundary bypass. It should not be treated as an Important-class kernel issue.

5. One-sentence report phrase
A memory leak in the ASoC SOF topology loading error path can leak `tplg_files` on repeated failed dummy topology loads, but triggering normally requires privileged control of topology or driver loading and the impact is limited to potential resource-exhaustion DoS.

6. Manual review recommendation
NO MANUAL CHECK NEEDED.
This is a small privileged error-path memory leak with no memory corruption primitive and no network or unprivileged reachability in typical deployments.

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

Patch: ASoC: SOF: topology: fix memory leak in snd_sof_load_topology
Commit: 6ed7787c43ecf4ae27a3e700cab53a1ed646c7f8
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6ed7787c43ecf4ae27a3e700cab53a1ed646c7f8

Commit description:

When the topology filename contains "dummy" and tplg_cnt is 0, the
function returns -EINVAL directly without freeing the tplg_files
allocated by kcalloc() at line 2497. This leaks memory on every
such topology load attempt.

Fix this by setting ret = -EINVAL and jumping to the out: label,
which already handles the kfree(tplg_files) cleanup.

Fixes: 99c1592 ("ASoC: SOF: don't check the existence of dummy topology")
Cc: stable@vger.kernel.org
Signed-off-by: Zhao Dongdong <zhaodongdong@kylinos.cn>
Acked-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/tencent_3EED6D778DC52C3703A2D1EE8119372E8E08@qq.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  sound/soc/sof/topology.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=6ed7787c43ecf4ae27a3e700cab53a1ed646c7f8

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

The original Linux kernel CVE announcement for CVE-2026-72263 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72263

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:L/PR:H/UI:N/S:U/C:N/I:N/A:L
  The Best / paranoid CVSS vector: AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS score: 4.4

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: 0

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).