Vulnerabilities
- CVSS
- 5.5 Medium
- Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H- EPSS
- 0.12%
- Risk score
- 1.3
- Published
- 2026-05-06
- Status
- Published
In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode
Commit 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation
request when device is disconnected") relies on
pci_dev_is_disconnected() to skip ATS invalidation for
safely-removed devices, but it does not cover link-down caused
by faults, which can still hard-lock the system.
For example, if a VM fails to connect to the PCIe device,
"virsh destroy" is executed to release resources and isolate
the fault, but a hard-lockup occurs while releasing the group fd.
Call Trace:
qi_submit_sync
qi_flush_dev_iotlb
intel_pasid_tear_down_entry
device_block_translation
blocking_domain_attach_dev
__iommu_attach_device
__iommu_device_set_domain
__iommu_group_set_domain_internal
iommu_detach_group
vfio_iommu_type1_detach_group
vfio_group_detach_container
vfio_group_fops_release
__fput
Although pci_device_is_present() is slower than
pci_dev_is_disconnected(), it still takes only ~70 µs on a
ConnectX-5 (8 GT/s, x2) and becomes even faster as PCIe speed
and width increase.
Besides, devtlb_invalidation_with_pasid() is called only in the
paths below, which are far less frequent than memory map/unmap.
1. mm-struct release
2. {attach,release}_dev
3. set/remove PASID
4. dirty-tracking setup
The gain in system stability far outweighs the negligible cost
of using pci_device_is_present() instead of pci_dev_is_disconnected()
to decide when to skip ATS invalidation, especially under GDR
high-load conditions.
A flaw was found in the Linux kernel. When handling PCIe devices in scalable mode, the kernel may attempt to flush the device IOTLB (Input/Output Translation Lookaside Buffer) without verifying if the PCIe device is still accessible after a link-down fault. This improper handling during resource release, such as when a virtual machine is destroyed, can lead to a system hard-lock, resulting in a Denial of Service.
Coverage 7
vulnerability
Multiple vulnerabilities have been discovered in the Linux kernel of Ubuntu. Some of these vulnerabilities allow for privilege escalation, data confidentiality breaches, and data integrity compromise. The vulnerabilities…
threat-intel
Multiple vulnerabilities have been discovered in the SUSE Linux kernel. These vulnerabilities can lead to data confidentiality and integrity breaches, policy circumvention, and denial of service conditions. The affected…
vulnerability
Multiple vulnerabilities have been discovered in the Linux kernel of Ubuntu. Several of these vulnerabilities allow for privilege escalation, data confidentiality breaches, and a security issue not specified by the publi…
vulnerability
Multiple vulnerabilities have been discovered in the Linux kernel of Ubuntu. Some of these vulnerabilities allow for privilege escalation, data confidentiality breaches, and data integrity compromise. These vulnerabiliti…
vulnerability
Multiple vulnerabilities have been discovered in the SUSE Linux kernel. Several of these vulnerabilities can lead to data confidentiality and integrity breaches, as well as the circumvention of security policies and deni…
vulnerability
Multiple vulnerabilities have been discovered in the SUSE Linux kernel. Some of these vulnerabilities allow for data confidentiality and integrity breaches, as well as bypassing security policies and causing denial of se…
threat-intel
Multiple vulnerabilities have been discovered in the Linux kernel of Ubuntu. Some of these vulnerabilities allow for privilege escalation, data confidentiality breaches, and denial of service attacks. The vulnerabilities…
Advisories and references