[CVE-2026-89582][MODERATE 7.0] bnx2x: fix double free in bnx2x_init_firmware() error path

[CVE-2026-89582][MODERATE 7.0] bnx2x: fix double free in bnx2x_init_firmware() error path

[AL-KERNEL]

CVE: CVE-2026-89582
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: YES
Patch: bnx2x: fix double free in bnx2x_init_firmware() error path
Commit: dc98e727b9cfc5e19c796bf893878153f00b222b
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=dc98e727b9cfc5e19c796bf893878153f00b222b
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-89582
Analysis date: Sat, 12 Sep 2026 03:37:39 -0400
ActionableScore: 5
ActionableScore lower bound: unknown
Actionable bucket: Actionable Moderate / Strong Important candidate requiring manual review
Manual review required: YES

Summary:
No one-sentence report phrase was found.

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

The original Linux kernel CVE announcement for CVE-2026-89582 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-89582

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-2026-89582	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-89582 CHECK WITH IMPACT FROM ORIG NN IMPORTANT	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H';CWE-415;*CWE-672;*CWE-664;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H';BEST CVSS score: '7';DESCR 'A double-free in bnx2x_init_firmware() can occur on the firmware initialization error path because bp init_ops_offsets, bp init_ops, and bp init_data are freed without being cleared. If bnx2x_release_firmware() later runs from device removal or the driver state machine, the same allocations can be freed again, creating a kernel memory corruption condition. For the CVSS the PR:L is used in the paranoid score because a reduced capability service account or delegated device management path could potentially influence driver reprobe or failure handling, although the common real world trigger needs administrator control. The issue is local and not network reachable because it occurs during driver initialization or cleanup rather than packet processing. Impact is at least denial of service via kernel crash and in the paranoid case may include confidentiality and integrity impact due to a double-free memory corruption primitive.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate / Strong Important candidate requiring manual review (with actual score 5)	YES	REMOTE DANGER INIT ERRORPATH UAF NETWORK LINUS KPANIC  KPANIC DECREASED_TO_MODERATE70_BASED_ON_ACTIONABLESCORELOWERTHAN6	NO	NO	checked

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

ActionableScore=5
PrimitiveClass=CLASS_B
RealUAF=YES
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=NO
ImportantCandidate=YES
ManualReview=REQUIRED
AutoDowngradeAllowed=NO

1. ActionableScore

* Raw conservative score: 4
* Conservative score: 5
* Applied conservative floor/cap: Real UAF FLOOR 5 applied because the patch establishes a concrete repeated free on the exact same references after the first free may end object lifetime.
* Raw paranoid score: 5
* Paranoid score: 5
* Applied paranoid floor/cap: no additional floor or cap changed the paranoid score.
* Final recommended bucket: **Actionable Moderate / Strong Important candidate requiring manual review**::

2. Signal breakdown

Positive signals:

* +2 Real UAF / active lifetime violation: `bp->init_ops_offsets`, `bp->init_ops`, and `bp->init_data` are freed in the `bnx2x_init_firmware()` error path and remain reachable for a later cleanup path.
* +1 Concrete repeated release/free operation: the same exact pointers can later be passed again to `kfree()` from `bnx2x_release_firmware()`.
* +1 Reliable kernel crash / strong DoS: a double free in kernel heap memory can realistically corrupt allocator state or crash the kernel during cleanup.

Paranoid-only signal:

* +1 Paranoid repeated-free leverage: the second `kfree()` is a concrete lifetime-mutating operation through storage whose original allocation may already have ended. This is stronger than a shallow stale dereference, but still not enough for CLASS_A without controlled reclaim or directed corruption.

Non-awarded signals:

* +0 Controlled reclaim not demonstrated.
* +0 Arbitrary or directed kernel write not demonstrated.
* +0 Confidentiality and integrity bonuses not awarded because no disclosure path, controlled overwrite, credential corruption, or protected object modification is established.
* +0 Remote reachability not established. The bug is in firmware initialization and cleanup, not packet processing.
* +0 Structured stale-object leverage not separately awarded because the meaningful extra fact is already counted as concrete repeated free.
* +0 Weak LPE not separately awarded for the same repeated-free fact.
* +0 Extra Availability not awarded because the same crash is already counted once.
* +0 Race penalty not applied because this is an ordered error-path and cleanup sequence, not a timing race.
* +0 Host-admin penalty not applied because host-admin-only reachability is plausible but not positively established as the only complete trigger path in the supplied evidence.

Repeated-release checks:

* First release can end lifetime: yes. `kfree(ptr)` can free the allocation.
* Exact same reference survives: yes. the patch adds `ptr = NULL`, proving the non-NULL stale pointer previously survived.
* Second operation is a real lifetime/free mutation: yes. later `bnx2x_release_firmware()` frees the same pointers unconditionally.
* +1 Concrete repeated release/refcount awarded: yes.
* Paranoid repeated-refcount/free leverage +1 awarded: yes.
* FLOOR 5 applied: yes.

3. Reachability analysis

The directly supported trigger is local driver/device lifecycle handling: firmware initialization fails, then firmware cleanup later runs through remove or the driver state machine. Ordinary network traffic is not shown to reach the vulnerable operation, so this is not a direct remote packet-processing issue.

The common practical trigger likely involves driver probe, firmware availability, device reset, remove, reprobe, or other device-management operations. Those are often host-admin-controlled, but the supplied evidence does not prove that host-admin-equivalent privilege is strictly required for every complete path, because the commit also mentions the function state machine and not only manual driver removal.

HostAdminRequired is therefore UNKNOWN rather than YES or NO. NamespaceScopedPrivilege is NO because no namespace-scoped capability path is established. No prior namespace setup or attacker-created object path is shown. Special Broadcom bnx2x hardware or device presence is required, but this is not treated as rare physical-only hardware from the supplied evidence. No hard race is involved.

4. Primitive and severity interpretation

The exact primitive is a kernel double free of three firmware-related allocations in the bnx2x driver. This is a real lifetime violation and a CLASS_B kernel corruption primitive, not merely a warning or passive bookkeeping issue.

This is not an ordinary stale cleanup dereference. It matches the stronger repeated lifetime mutation pattern:

A. ordinary stale cleanup dereference: stale pointer is only read or faults during cleanup.

B. second lifetime/free mutation through a potentially dangling object: `kfree()` is called once in the init error path, the same pointer remains non-NULL, and a later cleanup path can call `kfree()` again on the same address.

This case is B.

The demonstrated consequence is kernel memory corruption and likely crash or DoS. The speculative consequence is stronger exploitation through allocator state corruption, but controlled reclaim, arbitrary read/write, callback control, and privilege escalation are not established. PrimitiveClass is CLASS_B rather than CLASS_A.

ImportantCandidate is YES because a concrete repeated free through potentially dangling references leaves meaningful Important-vs-Moderate exploitation leverage unresolved. AutoDowngradeAllowed is NO because automatically treating this as ordinary crash-only cleanup would discard a real repeated lifetime mutation primitive. Operationally, this should be handled as Actionable Moderate at minimum with required manual security review.

5. One-sentence report phrase

A double-free in the bnx2x firmware initialization error path can leave freed firmware buffers reachable for later cleanup, causing kernel heap lifetime corruption and possible DoS, with stronger exploitation impact unresolved.

6. Manual review recommendation

MANUAL CHECK REQUIRED

Reason: this is a concrete double free of kernel heap allocations, and the second `kfree()` performs a real lifetime mutation on potentially freed storage even though controlled exploitation is not demonstrated.

7. Call-site confidence

Call-site confidence: high

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

Patch: bnx2x: fix double free in bnx2x_init_firmware() error path
Commit: dc98e727b9cfc5e19c796bf893878153f00b222b
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=dc98e727b9cfc5e19c796bf893878153f00b222b

Commit description:

bnx2x_init_firmware() frees bp->init_ops, bp->init_data and
bp->init_ops_offsets in its error path without setting them to NULL.
The cleanup function bnx2x_release_firmware() frees the same three
pointers unconditionally, so if init_firmware fails and
release_firmware is later called (e.g. from __bnx2x_remove or through
the function state machine), all three are freed a second time.

Set each pointer to NULL after kfree() in the error path so that the
subsequent kfree(NULL) in bnx2x_release_firmware() is a safe no-op.

Fixes: 94a78b7 ("bnx2x: Separated FW from the source.")
Cc: stable@vger.kernel.org
Signed-off-by: Jiangshan Yi <yijiangshan@kylinos.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260815122149.951215-1-yijiangshan@kylinos.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.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=dc98e727b9cfc5e19c796bf893878153f00b222b

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

The original Linux kernel CVE announcement for CVE-2026-89582 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-89582

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:L/I:L/A:H
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
  The Best / paranoid CVSS score: 7

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: 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: YES
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).