# CVE-2026-98965: ice: Restore Ordered MMIO Writes for Tx Doorbells


- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 23 Oct 2026
- **Updated:** 24 Oct 2026
- **Also known as:** BELL-CVE-2026-98965, DEBIAN-CVE-2026-98965, GHSA-272r-g6c6-94w3, UBUNTU-CVE-2026-98965

## What is CVE-2026-98965?

CVE-2026-98965 is a high-severity vulnerability in Linux, published on 23 Oct 2026. 

### Official description

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

ice: Restore Ordered MMIO Writes for Tx Doorbells

The DQL accounting state which tracks the number of bytes queued for the
NIC to transmit, namely dql->num_queued, is updated by the ICE driver
when it invokes __netdev_tx_sent_queue(). Subsequently the driver
updates the hardware queue tail allowing the NIC to begin processing the
work queue. The queue accounting update should be ordered before the NIC
begins transmitting descriptors.

The transmit path currently updates the hardware doorbell using
writel_relaxed(), which (on arm64) does not provide the same ordering
guarantees between writes to normal memory and writes to MMIO registers
that writel() does. This introduces a potential race where the NIC
begins transmitting descriptors before the dql->num_queued update is
globally visible. If the NIC finishes before the update is observed by
dql_completed(), it detects an invalid state where more bytes have been
completed than have been queued. When this happens the following BUG_ON
is triggered.

  BUG_ON(count > num_queued - dql->num_completed);

This has been observed and manifests as the following crash (note that
the trace has been trimmed) in an environment with sustained network
load that uses an Intel Corporation Ethernet Controller E810-XXV for SFP
(rev 02) on an arm64 machine. Replacing writel_relaxed() with writel()
in a test kernel eliminated the crash in the user's workload, which
previously reproduced the issue reliably.

  kernel BUG at lib/dynamic_queue_limits.c:99

Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
pc : dql_completed+0x268/0x2a0
lr : ice_clean_tx_irq+0x1d4/0x620 [ice]
Call trace:
dql_completed+0x268/0x2a0 (P)
ice_napi_poll+0x94/0x520 [ice]
__napi_poll+0x48/0x3f0
net_rx_action+0x194/0x420

This restores the behaviour prior to commit ccde82e90946 ("ice: add E830
Earliest TxTime First Offload support"), which changed the notification
mechanism from writel() to writel_relaxed().

## Which versions are affected by CVE-2026-98965?


## How do I fix CVE-2026-98965?

Upgrade to a fixed version.

## Is CVE-2026-98965 being exploited?

There is no known exploitation of CVE-2026-98965 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98965 and fix it if it is affected.

What it is: CVE-2026-98965 is a high-severity vulnerability in Linux, published on 23 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-98965 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-98965/ (Markdown: https://insights.sbomify.com/CVE-2026-98965/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98965
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98965
- OSV: https://osv.dev/vulnerability/CVE-2026-98965

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98965/
Summaries are generated and may contain mistakes; the official description above is the record.