# CVE-2026-89567

## Summary

- **CVE ID:** CVE-2026-89567
- **Severity:** UNKNOWN
- **CVSS Score:** 1.51
- **CWE:** N/A
- **Published:** Sep 11, 2026
- **Last Modified:** Sep 16, 2026

## Description

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

jbd2: bound shrinker scans by examined checkpoint buffers

The jbd2 shrinker currently accounts only checkpoint buffers that it
successfully releases against nr_to_scan.  Busy buffers therefore do not
consume the scan budget.

If a checkpoint transaction contains mostly busy buffers, the shrinker
can scan its entire checkpoint list while holding journal->j_list_lock.
Large checkpoint lists can result in excessive lock hold times and leave
other CPUs spinning on j_list_lock, causing soft lockups or RCU stalls.

Pass nr_to_scan into journal_shrink_one_cp_list() and decrement it for
every buffer examined, including busy buffers.  Pass NULL from checkpoint
cleanup paths so their existing full-list behavior is preserved.

This restores the scan-budget semantics that existed before
journal_shrink_one_cp_list() was changed to always scan a complete
checkpoint list.

## Affected Products

- Linux — Linux (b98dba273a0e47dbfade89c9af73c5b012a4eabb)
- Linux — Linux (9c31bb2684f8035beca0275349d19d679b679ffb)
- Linux — Linux (5fda50e262e65bd553ff777c4b280afd1495a18b)
- Linux — Linux (557fda9ed70ebf8eda2620ba3d746215285a1303)
- Linux — Linux (5.15.129)
- Linux — Linux (6.1.50)
- Linux — Linux (6.4.13)
- Linux — Linux (6.5)
- Linux — Linux (0)
- Linux — Linux (6.12.109)
- Linux — Linux (6.18.50)
- Linux — Linux (7.2.4)
- Linux — Linux (7.3-rc1)

## References

- [CNA](https://git.kernel.org/stable/c/edf5fcd0469b7467bd5b37a79502c8d9c3257dbb)
- [CNA](https://git.kernel.org/stable/c/71c6b872c746465fa4b5def239cb296173ca8216)
- [CNA](https://git.kernel.org/stable/c/c2c0fb364685b8996c357d3b050394959b29d6e0)
- [CNA](https://git.kernel.org/stable/c/15cb16496446b94e67f7abcb049b8e2c75cd3d02)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.20%
- **EPSS Percentile:** 10.0

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-17._