SB20260727291 - Improper handling of exceptional conditions in Linux kernel iommu iommufd driver

Description

This security bulletin contains information about 1 vulnerability.

1) Improper handling of exceptional conditions (CVE-ID: CVE-2026-64290)

CWE-ID: CWE-755 - Improper Handling of Exceptional Conditions

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper exception handling in iommufd_fault_fops_read() when handling a copy_to_user() failure while reading fault events. A local user can trigger a failing read operation to cause a denial of service.

The issue can lead to an infinite retry loop that spins the reader at 100% CPU while holding fault->mutex.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/172fc8b19825a0f5884c38f2289188284e2d45ee
• https://git.kernel.org/stable/c/5539da127d03c1f6c2e2a49fdfbe331a0ccbdea8
• https://git.kernel.org/stable/c/f66c16b175509642ee7082df57c9bf3deaebae1a