---
cve: "CVE-2026-89834"
severity: "LOW"
cvss: 3.1
epss: "0.2%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-09-16 11:16:50"
tags: [cve, security, low]
source: tsecurity.de CVE-Dossier
exported: "2026-09-20T20:05:01+02:00"
---

# CVE-2026-89834

> 3.1 LOW

## Beschreibung

In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix to migrate all curseg types during free_segment_range

In free_segment_range(), the curseg evacuation loop only iterates up to
NR_CURSEG_PERSIST_TYPE (0..5), missing non-persistent in-memory curseg
types such as CURSEG_COLD_DATA_PINNED and CURSEG_ALL_DATA_ATGC.

Even though these in-memory curseg types are not saved in the on-disk
checkpoint header, they still occupy active physical segments at runtime.
If an active in-memory curseg happens to be allocated within the segment
range being truncated during filesystem shrink, failing to evacuate it
will cause subsequent writes to the curseg attempting out-of-bounds I/O
on the truncated storage range.

Fix this by expanding the curseg evacuation loop upper bound to
NR_CURSEG_TYPE to ensure all active curseg types are safely migrated
out of the target range.

## Patch verfügbar (OSV)

- Kernel ≥ 6.12.110
- Kernel ≥ 6.18.51
- Kernel ≥ 7.2.5

## Referenzen

- <https://git.kernel.org/stable/c/3b85edf3391f3e1f624f409a7d2d239885f567b7>
- <https://git.kernel.org/stable/c/b8ae1228c153622afa71a179c9d4dc268117e0f0>
- <https://git.kernel.org/stable/c/b9776094aa7118e8e5dfdcd791ffc8330c5ca408>
- <https://git.kernel.org/stable/c/8ec06f50ddd8d201bd7e55b896ae28ed9d4cb7d1>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-89834) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_