CVE-2026-46009: PCI: endpoint: pci-epf-ntb: Remove duplicate resource teardown
In the Linux kernel, the following vulnerability has been resolved:
PCI: endpoint: pci-epf-ntb: Remove duplicate resource teardown
epfntbepcdestroy() duplicates the teardown that the caller is supposed to do later. This leads to an oops when .allowlink fails or when .droplink is performed. Remove the helper.
Also drop pciepcput(). EPC device refcounting is tied to configfs EPC group lifetime, and pciepcput() in the .droplink path is sufficient.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.141.1-1
Event History
Frequently Asked Questions
What conditions trigger the kernel crash?
An oops can occur when the PCI endpoint function NTB driver's .allow_link operation fails or when its .drop_link operation is performed. The issue is caused by duplicate resource teardown in the affected path.
Which systems are exposed?
Systems using the Linux kernel PCI endpoint NTB function driver are implicated. The provided data also identifies Microsoft azl3 kernel 6.6.139.1-1 as affected software.
Is authentication or user interaction required to trigger the issue?
The supplied vector lists no privileges required and no user interaction required. It also indicates network attack vector and low attack complexity, but the provided description does not specify the exact remote interface or request needed to reach the vulnerable driver path.
What is the impact of successful exploitation?
The reported impact is high availability impact, with no reported confidentiality or integrity impact. The failure manifests as a kernel oops.