CVE-2026-93815 - Vulnerability Details

- net: au1000: move free_irq out of the close-time spinlocked section

Description

In the Linux kernel, the following vulnerability has been resolved:

net: au1000: move free_irq out of the close-time spinlocked section

au1000_close() calls free_irq() while aup->lock is still held with
spin_lock_irqsave(). free_irq() can sleep because it takes the IRQ
descriptor request mutex, so it does not belong inside the close-time
spinlocked section.

This was found by our static analysis tool and then confirmed by manual
review of the in-tree au1000_close() .ndo_stop path. The reviewed path
keeps aup->lock held across the MAC reset, queue stop and
free_irq(dev->irq, dev).

A directed runtime validation kept that ndo_stop carrier and the same
free_irq(dev->irq, dev) operation under the driver lock. Lockdep reported
"BUG: sleeping function called from invalid context" and "Invalid wait
context" while free_irq() was taking desc->request_mutex, with
au1000_close() and free_irq() on the stack.

Drop aup->lock before freeing the IRQ. The protected close-time work still
stops the device and queue before IRQ teardown, but the sleepable IRQ core
path now runs outside the spinlocked section.

Published: 2026-09-24

Score: n/a

EPSS: n/a

KEV: No

Impact:

Action:

Analysis

Impact

This bug resides in the Linux kernel au1000 network driver. The driver’s close routine calls free_irq while still holding a spinlock, which causes the kernel to sleep in a non‑sleepable context. This mismatch triggers lockdep errors such as "BUG: sleeping function called from invalid context" and can lead to a kernel panic or other instability. The flaw fits the concurrency weakness described by CWE‑727.

Affected Systems

All Linux kernel releases that contain the au1000 driver are potentially affected. No specific kernel version list is provided in the vendor data, so any build exposing this driver is at risk.

Risk and Exploitability

The CVSS and EPSS scores are not available; the vulnerability is not listed in the CISA KEV catalog. The flaw is a kernel‑level concurrency issue that can cause a crash or denial of service. An attacker must have sufficient privileges to trigger the close sequence (e.g., by bringing down the device). Although exploitation evidence is lacking, the potential impact is high due to kernel instability.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Linux

unaffected

Version	Status	Constraints
`1da177e4c3f41524e886b7f1b8a0c1fc7321cac2`	affected	< 4536667fba8ddbaff2f2a135080ae6aabf737b5e
`1da177e4c3f41524e886b7f1b8a0c1fc7321cac2`	affected	< fc2233f1ab2a1ca562869bca6987d7477671388c
`1da177e4c3f41524e886b7f1b8a0c1fc7321cac2`	affected	< f48763beab4eea41fc480c9702ec6eebe8d75e4f
`0`	affected	< 6.12.111
`0`	affected	< 6.18.53

Linux

affected

Version	Status	Constraints
`6.12.111`	unaffected	≤ 6.12.*
`6.18.53`	unaffected	≤ 6.18.*
`7.2`	unaffected	≤ *

No data.

Vendor Product Confidence Versions

Linux

Linux Kernel

99%

Version	Status	Scheme	Platform
`[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,4536667fba8ddbaff2f2a135080ae6aabf737b5e)`	affected	code_commit	—
`[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,fc2233f1ab2a1ca562869bca6987d7477671388c)`	affected	code_commit	—
`[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,f48763beab4eea41fc480c9702ec6eebe8d75e4f)`	affected	code_commit	—
`[0,6.12.111)`	affected	semver	—
`[0,6.18.53)`	affected	semver	—

Linux

Linux Kernel

99%

Version	Status	Scheme	Platform
`[6.12.111,6.12.*]`	unaffected	generic	—
`[6.18.53,6.18.*]`	unaffected	generic	—
`[7.2,*]`	unaffected	generic	—

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Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

Apply the kernel patch that moves free_irq out of the spinlocked section (commits 4536667fba8ddbaff2f2a135080ae6aabf737b5e or later).
If the patch cannot be applied, unload or disable the au1000 driver to prevent the close routine from executing.
Configure lockdep to warn on "sleeping function called from invalid context" and monitor kernel logs for related panics; apply fix promptly when detected.

Generated by OpenCVE AI on September 25, 2026 at 04:48 UTC.

Tracking

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Advisories

No advisories yet.

No CVSS v4.0

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://git.kernel.org/stable/c/4536667fba8ddbaff2f2a135080ae6aabf737b5e
https://git.kernel.org/stable/c/f48763beab4eea41fc480c9702ec6eebe8d75e4f
https://git.kernel.org/stable/c/fc2233f1ab2a1ca562869bca6987d7477671388c

History

Fri, 25 Sep 2026 05:15:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-727

Thu, 24 Sep 2026 16:30:00 +0000

Type	Values Removed	Values Added
Description		In the Linux kernel, the following vulnerability has been resolved: net: au1000: move free_irq out of the close-time spinlocked section au1000_close() calls free_irq() while aup->lock is still held with spin_lock_irqsave(). free_irq() can sleep because it takes the IRQ descriptor request mutex, so it does not belong inside the close-time spinlocked section. This was found by our static analysis tool and then confirmed by manual review of the in-tree au1000_close() .ndo_stop path. The reviewed path keeps aup->lock held across the MAC reset, queue stop and free_irq(dev->irq, dev). A directed runtime validation kept that ndo_stop carrier and the same free_irq(dev->irq, dev) operation under the driver lock. Lockdep reported "BUG: sleeping function called from invalid context" and "Invalid wait context" while free_irq() was taking desc->request_mutex, with au1000_close() and free_irq() on the stack. Drop aup->lock before freeing the IRQ. The protected close-time work still stops the device and queue before IRQ teardown, but the sleepable IRQ core path now runs outside the spinlocked section.
Title		net: au1000: move free_irq out of the close-time spinlocked section
First Time appeared		Linux Linux linux Kernel
CPEs		cpe:2.3:o:linux:linux_kernel::::::::
Vendors & Products		Linux Linux linux Kernel
References		https://git.kernel.org/stable/c/4536667fba8ddbaff2f2a135080ae6aabf737b5e https://git.kernel.org/stable/c/f48763beab4eea41fc480c9702ec6eebe8d75e4f https://git.kernel.org/stable/c/fc2233f1ab2a1ca562869bca6987d7477671388c

Subscriptions

Linux Linux Kernel

MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2026-09-24T16:02:52.078Z

Updated: 2026-09-24T16:02:52.078Z

Reserved: 2026-09-18T17:59:28.791Z

Link: CVE-2026-93815

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-09-24T17:17:15.010

Modified: 2026-09-24T17:17:15.010

Link: CVE-2026-93815

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-09-25T05:00:10Z

Weaknesses

CWE-727

Impact

Affected Systems

Risk and Exploitability

Tracking

Subscriptions

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