# CVE-2022-49378: sfc: fix considering that all channels have TX queues

> A null pointer dereference in the sfc network driver causes a kernel crash when using separate TX channels, leading to denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Feb 2025
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-49378, GHSA-6gpm-qxpm-qmwf, UBUNTU-CVE-2022-49378

## What is CVE-2022-49378?

CVE-2022-49378 is a medium-severity vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

sfc: fix considering that all channels have TX queues

Normally, all channels have RX and TX queues, but this is not true if
modparam efx_separate_tx_channels=1 is used. In that cases, some
channels only have RX queues and others only TX queues (or more
preciselly, they have them allocated, but not initialized).

Fix efx_channel_has_tx_queues to return the correct value for this case
too.

Messages shown at probe time before the fix:
 sfc 0000:03:00.0 ens6f0np0: MC command 0x82 inlen 544 failed rc=-22 (raw=0) arg=0
 ------------[ cut here ]------------
 netdevice: ens6f0np0: failed to initialise TXQ -1
 WARNING: CPU: 1 PID: 626 at drivers/net/ethernet/sfc/ef10.c:2393 efx_ef10_tx_init+0x201/0x300 [sfc]
 [...] stripped
 RIP: 0010:efx_ef10_tx_init+0x201/0x300 [sfc]
 [...] stripped
 Call Trace:
  efx_init_tx_queue+0xaa/0xf0 [sfc]
  efx_start_channels+0x49/0x120 [sfc]
  efx_start_all+0x1f8/0x430 [sfc]
  efx_net_open+0x5a/0xe0 [sfc]
  __dev_open+0xd0/0x190
  __dev_change_flags+0x1b3/0x220
  dev_change_flags+0x21/0x60
 [...] stripped

Messages shown at remove time before the fix:
 sfc 0000:03:00.0 ens6f0np0: failed to flush 10 queues
 sfc 0000:03:00.0 ens6f0np0: failed to flush queues

## Which versions are affected by CVE-2022-49378?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49378?

Apply the vendor's patch.

## Is CVE-2022-49378 being exploited?

There is no known exploitation of CVE-2022-49378 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-49378 and fix it if it is affected.

What it is: CVE-2022-49378 is a medium-severity vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-49378 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2022-49378/ (Markdown: https://insights.sbomify.com/CVE-2022-49378/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49378
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49378
- OSV: https://osv.dev/vulnerability/CVE-2022-49378

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49378/
Summaries are generated and may contain mistakes; the official description above is the record.