[CVE-2026-72087][LOW] scsi: lpfc: Fix memory leak in lpfc_sli4_driver_resource_setup()

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

CVE: CVE-2026-72087
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: scsi: lpfc: Fix memory leak in lpfc_sli4_driver_resource_setup()
Commit: 299f5baa1321a0951cc3ebbacc72b67433a65391
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=299f5baa1321a0951cc3ebbacc72b67433a65391
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72087
Analysis date: Sun, 16 Aug 2026 02:15:10 -0400
ActionableScore: 1
ActionableScore lower bound: 0
Actionable bucket: Ordinary Moderate / Low-like. Auto-close candidate
Manual review required: YES

Summary:
An lpfc driver initialization error path can leak an `mboxq` object allocated from a mempool, but exploitation requires privileged local driver or HBA management and the practical impact is limited to possible resource-exhaustion DoS after repeated failed setup attempts.

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ABOUT THIS REPORT
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The original Linux kernel CVE announcement for CVE-2026-72087 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72087

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: YES

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
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CVE-2026-72087	LOW	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:H/UI:N/S:U/C:N/I:N/A:H';*CWE-401;*CWE-772;**CWE-400;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.1';DESCR 'lpfc_sli4_driver_resource_setup can leak an mboxq object allocated from a mempool when some early error exits are taken after driver resource setup has partially progressed. This is a resource leak in the lpfc driver initialization path rather than a memory corruption primitive. For the CVSS the PR:H because reliable triggering normally requires administrative control over driver probe, reload, reset, or Fibre Channel adapter recovery paths. The issue is not network reachable and is tied to local driver or hardware management operations. Impact is denial of service only through possible resource exhaustion after repeated failed setup attempts.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like. Auto-close candidate (with actual score 1)	YES	INIT LEAK ERRORPATH UAF HARDWARE 	NO	NO	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=1
ActionableScoreLower=0

## 1. ActionableScore

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

## 2. Signal breakdown

Triggered signals:

* Availability impact realistic: +1
  Repeated failed driver setup attempts can leak `mboxq` objects and may eventually contribute to resource exhaustion.

Subtracting signals:

* Requires admin/root/CAP_* in typical deployments: -2
  Reliable triggering normally requires control over lpfc driver probe, reload, reset, or Fibre Channel HBA recovery paths.

* Physical-only or rare hardware-only condition: -2 conservative, -1 paranoid
  The affected path is specific to Broadcom Emulex lpfc Fibre Channel hardware and driver initialization or recovery behavior.

Not awarded:

* No generic memory corruption signal. This is a leak, not UAF, double free, OOB write, type confusion, or refcount takeover.
* No privilege escalation signal. No reclaim, overwrite, stale callback, object confusion, or sensitive boundary bypass is shown.
* No confidentiality or integrity signal. The leaked object is not exposed and no data corruption primitive is indicated.
* No reliable strong DoS signal in the conservative score. A single trigger leaks a small object and does not directly crash the kernel.

Call-site confidence: high. The patch shows the affected allocation lifetime and the corrected `mempool_free()` placement inside `lpfc_sli4_driver_resource_setup()`.

## 3. Reachability analysis

The bug is reachable through the lpfc driver resource setup path, mainly during driver initialization, probe, reset, or recovery after partial setup failure. In normal deployments, an attacker would need administrative control over the host driver or device-management path to repeatedly exercise the failing branch.

Namespaces and containers do not normally reduce the privilege requirement, because Fibre Channel HBA management and driver reload/reset are host-level operations. The issue is not network reachable in the usual sense. Firmware or hardware error conditions may influence whether the error path is reached, but the patch does not show an externally controllable firmware-mediated attack path.

## 4. Severity interpretation

This behaves like an ordinary Low or low Moderate resource leak, not an Important-class kernel vulnerability. The realistic impact is limited availability degradation through repeated leaks in a privileged driver setup path.

Theoretical resource exhaustion is possible if the error path can be triggered repeatedly, but there is no evidence of memory corruption, privilege escalation, sensitive data exposure, or cross-boundary policy bypass.

## 5. One-sentence report phrase

An lpfc driver initialization error path can leak an `mboxq` object allocated from a mempool, but exploitation requires privileged local driver or HBA management and the practical impact is limited to possible resource-exhaustion DoS after repeated failed setup attempts.

## 6. Manual review recommendation

NO MANUAL CHECK NEEDED

NO MANUAL CHECK REQUIRED COULD BE AUTOCLOSED because this is a privileged local resource leak with no demonstrated memory corruption, no network reachability, no confidentiality or integrity impact, and no plausible privilege escalation primitive.

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

Patch: scsi: lpfc: Fix memory leak in lpfc_sli4_driver_resource_setup()
Commit: 299f5baa1321a0951cc3ebbacc72b67433a65391
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=299f5baa1321a0951cc3ebbacc72b67433a65391

Commit description:

The memory allocated for mboxq using mempool_alloc() is not freed in
some of the early exit error paths. Fix that by moving the
mempool_free() call to an earlier point after last use.

Fixes: d79c9e9 ("scsi: lpfc: Support dynamic unbounded SGL lists on G7 hardware.")
Cc: stable@vger.kernel.org
Signed-off-by: Abdun Nihaal <nihaal@cse.iitm.ac.in>
Reviewed-by: Justin Tee <justin.tee@broadcom.com>
Link: https://patch.msgid.link/20260707065304.949135-1-nihaal@cse.iitm.ac.in
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/scsi/lpfc/lpfc_init.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=299f5baa1321a0951cc3ebbacc72b67433a65391

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

The original Linux kernel CVE announcement for CVE-2026-72087 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72087

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:H/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS score: 4.1

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).