[CVE-2026-53279][LOW] drm/gma500/oaktrail_lvds: fix hang on init failure

[CVE-2026-53279][LOW] drm/gma500/oaktrail_lvds: fix hang on init failure

[AL-KERNEL]

CVE: CVE-2026-53279
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: drm/gma500/oaktrail_lvds: fix hang on init failure
Commit: 5fe9f505d8578852c30668567bc3ce52e776e8c7
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5fe9f505d8578852c30668567bc3ce52e776e8c7
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53279
Analysis date: Fri, 26 Jun 2026 16:56:32 -0400
ActionableScore: 0
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate / Low-like
Manual review required: NO

Summary:
An error path in `drm/gma500/oaktrail_lvds` can incorrectly destroy an existing I2C adapter after a late LVDS init failure, causing an indefinite driver initialization hang, but triggering is privileged, local, and hardware-specific.

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

The original Linux kernel CVE announcement for CVE-2026-53279 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53279

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-2026-53279	LOW	CHECK	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-404;CWE-703;CWE-667;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '4.4';DESCR 'The oaktrail LVDS init error path can try to destroy an I2C adapter that was obtained from an existing registered adapter instead of being allocated by the LVDS init path itself. Because i2c_get_adapter takes an extra reference, deregistering that adapter can wait indefinitely for the reference to be released and can hang driver initialization. For the CVSS the PR:H is used because reliable triggering normally requires administrative control over driver load, device bind, or hardware initialization paths. The issue is not network reachable and is tied to local graphics driver initialization on affected gma500 oaktrail systems. Impact is denial of service through an init hang, with no supported evidence of information disclosure or privilege escalation.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 0)  SKIP CVE-2026-53279  SKIP The Fixes patch not applied yet, so unlikely that actual: a57ebfc0b4da16a3f36bfebb158198aab3e340f8 YES  NO NO unknown 	MAYBE	SIMPLEFIX ERRORPATH HARDWARE LINUS 	-	-	checked

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

ActionableScore=0

## 1. ActionableScore

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

## 2. Signal breakdown

Triggered positive signals:

* Reliable kernel hang / DoS: +1
  The commit describes an indefinite hang during LVDS initialization failure because the driver attempts to deregister an already registered I2C adapter while an extra reference from `i2c_get_adapter()` is still held.

* Availability impact realistic: +1
  The affected path can hang driver initialization on impacted hardware. This is availability impact, but it appears local, hardware-specific, and tied to error handling during init.

Triggered negative signals:

* Requires admin/root/device-management control in typical deployments: -2
  Reliable triggering normally requires controlling driver load, device bind/unbind, boot/init paths, or inducing a late LVDS init failure. This is not normally available to an unprivileged local user.

* Physical-only or rare hardware-specific condition: -2
  The bug is specific to `drm/gma500/oaktrail_lvds`, an uncommon legacy graphics driver path and a specific LVDS/I2C init scenario.

No triggered high-risk signals:

* No remote/network reachability.
* No local unprivileged trigger shown.
* No UAF, double-free, OOB write, arbitrary write, page-cache corruption, or reclaim primitive shown.
* No plausible privilege escalation path supported by the patch.
* No security-boundary bypass or sensitive-object access.

Raw score is negative after penalties, normalized to 0.

## 3. Reachability analysis

The issue is reachable through a local graphics driver initialization or recovery path on affected gma500/oaktrail LVDS systems. In normal deployments, an attacker would need administrative control over module loading, device binding, boot-time hardware initialization, or a comparable privileged device-management path.

Namespaces and containers do not meaningfully lower the privilege requirement in the usual case, because this is not a namespace-exposed API such as netlink, io_uring, procfs, or an unprivileged syscall surface. The affected subsystem is not broadly deployed and depends on rare legacy hardware. Realistic exploitation is limited to causing or encountering an init failure condition on affected hardware.

## 4. Severity interpretation

This behaves like a low-end Moderate or Low-like DoS issue rather than an Important-class vulnerability. The bug is an ownership/error-handling mismatch for an I2C adapter reference, and the demonstrated consequence is an indefinite init hang. There is no evidence of attacker-controlled memory corruption, stale pointer reuse, object reclaim, information disclosure, or privilege escalation.

Theoretical impact beyond DoS is not supported by the patch context. The practical risk is mainly operational availability impact on rare hardware under privileged or boot-time conditions.

## 5. One-sentence report phrase

An error path in `drm/gma500/oaktrail_lvds` can incorrectly destroy an existing I2C adapter after a late LVDS init failure, causing an indefinite driver initialization hang, but triggering is privileged, local, and hardware-specific.

## 6. Manual review recommendation

NO MANUAL CHECK NEEDED

This can be auto-closed for urgent security triage purposes because it is a privileged, rare-hardware, DoS-only init hang with no supported memory corruption or privilege escalation primitive.

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

Patch: drm/gma500/oaktrail_lvds: fix hang on init failure
Commit: 5fe9f505d8578852c30668567bc3ce52e776e8c7
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5fe9f505d8578852c30668567bc3ce52e776e8c7

Commit description:

The LVDS init code looks up an I2C adapter using i2c_get_adapter() and
tries to read the EDID before falling back to allocating and registering
its own adapter.

The error handling does not separate these cases so on a late init
failure it will try to deregister and free also an adapter that had
previously been registered. Since i2c_get_adapter() takes another
reference to the adapter, deregistration hangs indefinitely while
waiting for the reference to be released.

Fix this by only destroying adapters allocated during LVDS init on
errors.

Fixes: a57ebfc ("drm/gma500: Make oaktrail lvds use ddc adapter from drm_connector")
Cc: stable@vger.kernel.org	# 6.0
Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Link: https://patch.msgid.link/20260508144446.59722-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/gpu/drm/gma500/oaktrail_lvds.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=5fe9f505d8578852c30668567bc3ce52e776e8c7

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

The original Linux kernel CVE announcement for CVE-2026-53279 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53279

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:H
  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).