# CVE-2025-40218: mm/damon/vaddr: do not repeat pte_offset_map_lock() until success

CVE-2025-40218 is fixed in 36 products on 1 platform, first by DEBIAN-CVE-2025-40218, released December 4, 2025. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2025-40218
- Priority: Routine
- CVSS: 4.1 (Moderate)
- EPSS: 0.0020
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 4, 2025
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-40218

## Description

In the Linux kernel, the following vulnerability has been resolved:  mm/damon/vaddr: do not repeat pte_offset_map_lock() until success  DAMON's virtual address space operation set implementation (vaddr) calls pte_offset_map_lock() inside the page table walk callback function.  This is for reading and writing page table accessed bits.  If pte_offset_map_lock() fails, it retries by returning the page table walk callback function with ACTION_AGAIN.  pte_offset_map_lock() can continuously fail if the target is a pmd migration entry, though.  Hence it could cause an infinite page table walk if the migration cannot be done until the page table walk is finished.  This indeed caused a soft lockup when CPU hotplugging and DAMON were running in parallel.  Avoid the infinite loop by simply not retrying the page table walk.  DAMON is promising only a best-effort accuracy, so missing access to such pages is no problem.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bpftool6.12 amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | bpftool6.12-debuginfo amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | dtb-aarch64 opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-64kb opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-64kb sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-azure opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-azure sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-default opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-default sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-default-base opensuse-leap 16.0 | 6.12.0-160000.9.1.160000.2.6 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-default-base sles 16.0 | 6.12.0-160000.9.1.160000.2.6 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-docs opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-docs sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-kvmsmall opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-kvmsmall sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-livepatch-6.12.55-74.119 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel-obs-build opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-obs-qa opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-obs-qa sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-rt opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-source opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-source sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-syms opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-syms sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel-zfcpdump opensuse-leap 16.0 | 6.12.0-160000.9.1 | [OPENSUSE-SU-2026:20145-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-20145-1.md) | Feb 2, 2026 |
| Linux | kernel-zfcpdump sles 16.0 | 6.12.0-160000.9.1 | [SUSE-SU-2026:20220-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-20220-1.md) | Feb 2, 2026 |
| Linux | kernel6.12 amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-debuginfo amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-debuginfo-common-aarch64 amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-debuginfo-common-x86_64 amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-devel amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-headers amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-libbpf amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-libbpf-debuginfo amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-libbpf-devel amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-libbpf-static amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-modules-extra amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-modules-extra-common amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-tools amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-tools-debuginfo amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | kernel6.12-tools-devel amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | linux Debian 13.5 (trixie) | 6.12.57-1 | [DEBIAN-CVE-2025-40218](https://patchblox.com/security/data/fix/linux/debian-cve-2025-40218.md) | Dec 4, 2025 |
| Linux | linux Debian 14 | 6.17.6-1 | [DEBIAN-CVE-2025-40218](https://patchblox.com/security/data/fix/linux/debian-cve-2025-40218.md) | Dec 4, 2025 |
| Linux | perf6.12 amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | perf6.12-debuginfo amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | python3-perf6.12 amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |
| Linux | python3-perf6.12-debuginfo amzn 2023 | 1:6.12.55-74.119.amzn2023 | [ALAS2023-2025-1316](https://patchblox.com/security/data/fix/linux/alas2023-2025-1316.md) | Dec 8, 2025 |

---

Data as of 2026-11-08T19:12:23Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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