CVE-2026-80894

/// Technical description

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

iommufd: Fix wrong hwpt passed to iommufd_auto_response_faults on replace

iommufd_hwpt_replace_device() calls:

iommufd_auto_response_faults(hwpt, old_handle);

passing the *new* hwpt together with the handle of

the device's *old* domain. This should be a parameter mismatch:

1. Semantically, iommufd_auto_response_faults(x, handle) scans

x->fault's deliver list and response xarray for groups matching

"handle". A group is queued under the hwpt that was attached at

fault-delivery time. old_handle is fetched *before* the domain switch,

so its group lives on old->fault, not on the new hwpt->fault.

2. Historically, the first argument was "old". The routine was

introduced by commit b7d8833677ba ("iommufd: Fault-capable hwpt

attach/detach/replace") as __fault_domain_replace_dev() in

fault.c, correctly calling iommufd_auto_response_faults(old, curr).

Commit fb21b1568ada ("iommufd: Make attach_handle

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References