CVE-2026-89445 — iommufd: Fix UAF in selftest IOPF reporting
In the Linux kernel, the following vulnerability has been resolved: iommufd: Fix UAF in selftest IOPF reporting IOMMUFD selftest TRIGGER_IOPF borrows an attach handle from gro…
Published: 2026-09-11 · CVSS: 8.8 · CVSS 3.1
In the Linux kernel, the following vulnerability has been resolved: iommufd: Fix UAF in selftest IOPF reporting IOMMUFD selftest TRIGGER_IOPF borrows an attach handle from group->pasid_array without synchronizing against PASID detach, then a concurrent iommu_report_device_fault() can dereference that borrowed handle's domain pointer after the detach erases the handle and frees the backing struct iommufd_attach_handle. TRIGGER_IOPF then dereferences the freed handle, causing a UAF. Fix by adding a iopf_rwsem in mock_dev to follow the expected design of a real driver. Hold its read side across the whole iommu_report_device_fault() call, and its write side around every path that attaches, detaches, or replaces a device domain. This can block new reports and drains in-flight reports before an old attach handle or the IOPF fault parameter can be removed. Also take the write side while registering a mock device, since it can invoke the mock driver's default-domain attach callback.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7