SB20260816143 - Improper control of a resource through its lifetime in Linux kernel arm arm-smmu-v3 driver

Description

This security bulletin contains information about 1 vulnerability.

1) Improper control of a resource through its lifetime (CVE-ID: CVE-2026-74573)

CWE-ID: CWE-664 - Improper control of a resource through its lifetime

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause stale ATC and IOTLB entries to persist.

The vulnerability exists due to improper handling of multiple stream IDs in arm_vsmmu_vsid_to_sid() in the arm-smmu-v3 iommufd code when processing vSID invalidation for a vDEVICE backed by a device with several stream IDs. A local user can trigger vSID invalidation that reaches only the first physical stream ID to cause stale ATC and IOTLB entries to persist.

The issue occurs because the mapping uses only master->streams[0] even when more than one stream ID is present.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/0acbc621341aca4eb94d9c2f43e1ab273ff088f0
• https://git.kernel.org/stable/c/3808bab5d95ae79e333e11f6a73d178e084c645d
• https://git.kernel.org/stable/c/c3b8ee84a965058b41275069d4696f37a8b14bf6