# CVE-2024-56760: PCI/MSI: Handle lack of irqdomain gracefully

> A missing check in the Linux kernel PCI/MSI layer causes a warning and potential instability on platforms lacking MSI support, 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:** 6 Jan 2025
- **Updated:** 11 May 2026
- **Also known as:** AZL-55044, BELL-CVE-2024-56760, DEBIAN-CVE-2024-56760, GHSA-7vgm-4f6w-wj5f, UBUNTU-CVE-2024-56760

## What is CVE-2024-56760?

CVE-2024-56760 is a medium-severity denial of service vulnerability in Linux kernel, published on 6 Jan 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:

PCI/MSI: Handle lack of irqdomain gracefully

Alexandre observed a warning emitted from pci_msi_setup_msi_irqs() on a
RISCV platform which does not provide PCI/MSI support:

 WARNING: CPU: 1 PID: 1 at drivers/pci/msi/msi.h:121 pci_msi_setup_msi_irqs+0x2c/0x32
 __pci_enable_msix_range+0x30c/0x596
 pci_msi_setup_msi_irqs+0x2c/0x32
 pci_alloc_irq_vectors_affinity+0xb8/0xe2

RISCV uses hierarchical interrupt domains and correctly does not implement
the legacy fallback. The warning triggers from the legacy fallback stub.

That warning is bogus as the PCI/MSI layer knows whether a PCI/MSI parent
domain is associated with the device or not. There is a check for MSI-X,
which has a legacy assumption. But that legacy fallback assumption is only
valid when legacy support is enabled, but otherwise the check should simply
return -ENOTSUPP.

Loongarch tripped over the same problem and blindly enabled legacy support
without implementing the legacy fallbacks. There are weak implementations
which return an error, so the problem was papered over.

Correct pci_msi_domain_supports() to evaluate the legacy mode and add
the missing supported check into the MSI enable path to complete it.

## Which versions are affected by CVE-2024-56760?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-56760?

Apply the vendor's patch.

## Is CVE-2024-56760 being exploited?

There is no known exploitation of CVE-2024-56760 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-2024-56760 and fix it if it is affected.

What it is: CVE-2024-56760 is a medium-severity denial of service vulnerability in Linux kernel, published on 6 Jan 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-2024-56760 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-2024-56760/ (Markdown: https://insights.sbomify.com/CVE-2024-56760/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-56760
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-56760
- OSV: https://osv.dev/vulnerability/CVE-2024-56760

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-56760/
Summaries are generated and may contain mistakes; the official description above is the record.