In the Linux kernel, the following vulnerability has been resolved: vfio/type1: prevent underflow of locked_vm via exec() When a vfio container is preserved across exec, the task does not change, but it gets a new mm with locked_vm=0, and loses the count from existing dma mappings. If the user later unmaps a dma mapping, locked_vm underflows to a large unsigned value, and a subsequent dma map request fails with ENOMEM in __account_locked_vm. To avoid underflow, grab and save the mm at the time a dma is mapped. Use that mm when adjusting locked_vm, rather than re-acquiring the saved task's mm, which may have changed. If the saved mm is dead, do nothing. locked_vm is incremented for existing mappings in a subsequent patch.
History

Wed, 17 Sep 2025 11:00:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Vendors & Products Linux
Linux linux Kernel

Mon, 15 Sep 2025 14:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: vfio/type1: prevent underflow of locked_vm via exec() When a vfio container is preserved across exec, the task does not change, but it gets a new mm with locked_vm=0, and loses the count from existing dma mappings. If the user later unmaps a dma mapping, locked_vm underflows to a large unsigned value, and a subsequent dma map request fails with ENOMEM in __account_locked_vm. To avoid underflow, grab and save the mm at the time a dma is mapped. Use that mm when adjusting locked_vm, rather than re-acquiring the saved task's mm, which may have changed. If the saved mm is dead, do nothing. locked_vm is incremented for existing mappings in a subsequent patch.
Title vfio/type1: prevent underflow of locked_vm via exec()
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2025-09-15T14:04:04.544Z

Updated: 2025-09-15T14:04:04.544Z

Reserved: 2025-09-15T13:59:19.064Z

Link: CVE-2023-53171

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-09-15T14:15:38.940

Modified: 2025-09-15T15:22:27.090

Link: CVE-2023-53171

cve-icon Redhat

No data.