# CVE-2026-89516

## Summary

- **CVE ID:** CVE-2026-89516
- **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:

sched_ext: Don't BUG_ON a destroyed DSQ in process_deferred_reenq_users

scx_bpf_dsq_reenq() queues a deferred reenq (dru) that runs from
run_deferred(), not ops.dispatch(). If the DSQ is destroyed before the dru
runs, process_deferred_reenq_users() sees dsq->id == SCX_DSQ_INVALID and
hits the BUG_ON. destroy_dsq() doesn't flush pending drus, so just skip.

tj: Read dsq->id once with READ_ONCE(). Reading it separately in the INVALID
    check and the BUG_ON would leave a window where destroy_dsq() can
    invalidate the id between the two reads and still trigger the BUG_ON.

## Affected Products

- Linux — Linux (84b1a0ea0b7c23dec240783a592e480780efe459)
- Linux — Linux (7.1)
- Linux — Linux (0)
- Linux — Linux (7.2.4)
- Linux — Linux (7.3-rc1)

## References

- [CNA](https://git.kernel.org/stable/c/c480961a1e790b46ffd8c20c4b6754d65ec6572d)
- [CNA](https://git.kernel.org/stable/c/8d8dd8ae89eaa78b37fc85528e926029f5facbdf)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.16%
- **EPSS Percentile:** 5.9

---
_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._