# CVE-2024-43876: PCI: rcar: Demote WARN() to dev_warn_ratelimited() in rcar_pcie_wakeup()

> Excessive kernel warnings during PCIe link state transitions can cause log flooding and potential system instability on Renesas R-Car platforms.

- **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:** 21 Aug 2024
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2024-43876, DEBIAN-CVE-2024-43876, GHSA-88v6-4cm5-82pp, UBUNTU-CVE-2024-43876

## What is CVE-2024-43876?

CVE-2024-43876 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 Aug 2024. 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: rcar: Demote WARN() to dev_warn_ratelimited() in rcar_pcie_wakeup()

Avoid large backtrace, it is sufficient to warn the user that there has
been a link problem. Either the link has failed and the system is in need
of maintenance, or the link continues to work and user has been informed.
The message from the warning can be looked up in the sources.

This makes an actual link issue less verbose.

First of all, this controller has a limitation in that the controller
driver has to assist the hardware with transition to L1 link state by
writing L1IATN to PMCTRL register, the L1 and L0 link state switching
is not fully automatic on this controller.

In case of an ASMedia ASM1062 PCIe SATA controller which does not support
ASPM, on entry to suspend or during platform pm_test, the SATA controller
enters D3hot state and the link enters L1 state. If the SATA controller
wakes up before rcar_pcie_wakeup() was called and returns to D0, the link
returns to L0 before the controller driver even started its transition to
L1 link state. At this point, the SATA controller did send an PM_ENTER_L1
DLLP to the PCIe controller and the PCIe controller received it, and the
PCIe controller did set PMSR PMEL1RX bit.

Once rcar_pcie_wakeup() is called, if the link is already back in L0 state
and PMEL1RX bit is set, the controller driver has no way to determine if
it should perform the link transition to L1 state, or treat the link as if
it is in L0 state. Currently the driver attempts to perform the transition
to L1 link state unconditionally, which in this specific case fails with a
PMSR L1FAEG poll timeout, however the link still works as it is already
back in L0 state.

Reduce this warning verbosity. In case the link is really broken, the
rcar_pcie_config_access() would fail, otherwise it will succeed and any
system with this controller and ASM1062 can suspend without generating
a backtrace.

## Which versions are affected by CVE-2024-43876?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-43876?

Apply the vendor's patch.

## Is CVE-2024-43876 being exploited?

There is no known exploitation of CVE-2024-43876 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-2024-43876 and fix it if it is affected.

What it is: CVE-2024-43876 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 Aug 2024. 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-2024-43876 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-2024-43876/ (Markdown: https://insights.sbomify.com/CVE-2024-43876/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-43876
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-43876
- OSV: https://osv.dev/vulnerability/CVE-2024-43876

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-43876/
Summaries are generated and may contain mistakes; the official description above is the record.
