# CVE-2026-89509

## Summary

- **CVE ID:** CVE-2026-89509
- **Severity:** UNKNOWN
- **CVSS Score:** 0
- **CWE:** N/A
- **Published:** Sep 11, 2026
- **Last Modified:** Sep 16, 2026

## Description

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

RDMA/ionic: Embed counter driver data in rdma_counter allocation

Commit 7e53b31acc7f ("RDMA/core: Create and destroy rdma_counter using
rdma_zalloc_drv_obj()") requires drivers implementing counter ops to
embed struct rdma_counter in a driver-specific struct, register its size
via INIT_RDMA_OBJ_SIZE, and provide a counter_init callback.

The ionic driver was merged without this adaptation, causing a NULL
pointer dereference in alloc_and_bind() since rdma_zalloc_drv_obj()
allocates zero bytes when size_rdma_counter is unset.

Consolidate struct ionic_counter into a new struct ionic_rdma_counter
that embeds struct rdma_counter, replace the xarray with a lightweight
ida for ID allocation, and add the required counter_init and
INIT_RDMA_OBJ_SIZE declarations.

## Affected Products

- Linux — Linux (ea4c399642b85dc30f44d90ee805c6a18fa03062)
- Linux — Linux (6.18)
- Linux — Linux (0)
- Linux — Linux (6.18.51)
- Linux — Linux (7.2.4)
- Linux — Linux (7.3-rc1)

## References

- [CNA](https://git.kernel.org/stable/c/c98197ee3cd28288da13dc9881bb9e74daa7cbbc)
- [CNA](https://git.kernel.org/stable/c/08b8630b557828aedb1d9ef0a6e2ec421f334ee2)
- [CNA](https://git.kernel.org/stable/c/cf3ebd89e754015625fee90aa938f6bc79a2c974)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.20%
- **EPSS Percentile:** 9.8

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