[CVE-2026-46144][LOW] RDMA/mana: Fix error unwind in mana_ib_create_qp_rss() [ Upstream

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

CVE: CVE-2026-46144
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: RDMA/mana: Fix error unwind in mana_ib_create_qp_rss() [ Upstream
Commit: 190e570cc0fc7f57eacf80d2b854ba54b4dfad6b
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=190e570cc0fc7f57eacf80d2b854ba54b4dfad6b
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-46144
Analysis date: Thu, 28 May 2026 05:59:38 -0400
ActionableScore: 2
ActionableScore lower bound: 1
Actionable bucket: Ordinary Moderate / Low-like
Manual review required: NO

Summary:
A local user with access to the mana RDMA verbs device can trigger an RSS QP creation error path that leaks vport RX steering state, potentially causing resource exhaustion or device-level availability degradation after repeated attempts.

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

The original Linux kernel CVE announcement for CVE-2026-46144 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-46144

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-2026-46144	LOW	CHECK	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H';CWE-459;*CWE-772;CWE-404;Other CVSS 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.5';DESCR 'mana RDMA RSS QP creation can leave vport RX steering enabled if mana_ib_cfg_vport_steering succeeds but copying the result to user data fails. A local user with access to the mana RDMA verbs device can trigger this error path during RSS QP creation by providing failing udata, causing persistent device or vport state leakage and possible resource exhaustion or networking degradation. For the CVSS the PR:L is used for the paranoid score because reliable triggering requires local code execution and RDMA device access, but not full administrator privileges when RDMA access is delegated. The issue is not network reachable by packet traffic. Impact is availability only, with no evidence of memory corruption, information disclosure, or privilege escalation.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 2)	YES	SIMPLEFIX LEAK NETWORK  DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3	NO	NO	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=2
ActionableScoreLower=1

## 1. ActionableScore

* Conservative score: **1**
* Paranoid score: **2**
* Final recommended bucket: **Ordinary Moderate / Low-like**::

## 2. Signal breakdown

* **Local unprivileged trigger: +1**
  A local process with access to the mana RDMA verbs device may trigger the failing `copy_to_udata` path during RSS QP creation.

* **Availability impact realistic: +1**
  The leaked `mana_ib_cfg_vport_steering()` state may persist and repeated failures could cause RDMA device state leakage, vport resource exhaustion, or networking degradation.

* **Rare AND difficult-to-reach subsystem/configuration: -1**
  The affected path requires Microsoft Azure Network Adapter RDMA support and access to the mana RDMA device. This is not a broad default kernel interface for ordinary local users.

No memory corruption, UAF, OOB write, arbitrary write, information leak, privilege escalation, or network packet trigger is supported by the patch.

## 3. Reachability analysis

The bug is reachable by a local user or process that can access the mana RDMA verbs interface and create RSS QPs. Containers or namespaces matter only if the RDMA device is delegated into the container or service context. The path is hardware and environment specific, mainly relevant to systems using the mana RDMA driver. It is not directly reachable by remote network traffic. Realistic exploitation would require repeated local triggering of the error unwind path to accumulate leaked vport steering state.

## 4. Severity interpretation

This behaves like an ordinary Moderate or Low-like resource/state leak. The realistic impact is availability degradation or resource exhaustion in a device-specific RDMA path. Theoretical memory corruption potential is not indicated by the patch, and there is no evidence of confidentiality impact, integrity impact, or privilege escalation.

## 5. One-sentence report phrase

A local user with access to the mana RDMA verbs device can trigger an RSS QP creation error path that leaks vport RX steering state, potentially causing resource exhaustion or device-level availability degradation after repeated attempts.

## 6. Manual review recommendation

**NO MANUAL CHECK NEEDED**

This is a constrained RDMA error-unwind resource leak with no evidence of memory corruption, privilege escalation, or remote reachability.

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

Patch: RDMA/mana: Fix error unwind in mana_ib_create_qp_rss() [ Upstream
Commit: 190e570cc0fc7f57eacf80d2b854ba54b4dfad6b
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=190e570cc0fc7f57eacf80d2b854ba54b4dfad6b

Changed files:
  drivers/infiniband/hw/mana/qp.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=190e570cc0fc7f57eacf80d2b854ba54b4dfad6b

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

The original Linux kernel CVE announcement for CVE-2026-46144 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-46144

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:L/UI:N/S:U/C:N/I:N/A:L
  The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS score: 5.5

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: 1
  Paranoid ActionableScore: 2

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).