# CVE-2024-40979: wifi: ath12k: fix kernel crash during resume > A kernel crash occurs in the ath12k WiFi driver during resume when DMA remap is unsupported, causing a denial of service. - **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 12 Jul 2024 - **Updated:** 3 Oct 2026 - **Also known as:** BELL-CVE-2024-40979, DEBIAN-CVE-2024-40979, GHSA-gvwx-6cpm-mjrj, ROOT-OS-UBUNTU-2204-CVE-2024-40979, UBUNTU-CVE-2024-40979 ## What is CVE-2024-40979? CVE-2024-40979 is a high-severity vulnerability in Linux kernel, published on 12 Jul 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: wifi: ath12k: fix kernel crash during resume Currently during resume, QMI target memory is not properly handled, resulting in kernel crash in case DMA remap is not supported: BUG: Bad page state in process kworker/u16:54 pfn:36e80 page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x36e80 page dumped because: nonzero _refcount Call Trace: bad_page free_page_is_bad_report __free_pages_ok __free_pages dma_direct_free dma_free_attrs ath12k_qmi_free_target_mem_chunk ath12k_qmi_msg_mem_request_cb The reason is: Once ath12k module is loaded, firmware sends memory request to host. In case DMA remap not supported, ath12k refuses the first request due to failure in allocating with large segment size: ath12k_pci 0000:04:00.0: qmi firmware request memory request ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 7077888 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 8454144 ath12k_pci 0000:04:00.0: qmi dma allocation failed (7077888 B type 1), will try later with small size ath12k_pci 0000:04:00.0: qmi delays mem_request 2 ath12k_pci 0000:04:00.0: qmi firmware request memory request Later firmware comes back with more but small segments and allocation succeeds: ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 262144 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288 ath12k_pci 0000:04:00.0: qmi mem seg type 4 size 65536 ath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288 Now ath12k is working. If suspend is triggered, firmware will be reloaded during resume. As same as before, firmware requests two large segments at first. In ath12k_qmi_msg_mem_request_cb() segment count and size are assigned: ab->qmi.mem_seg_count == 2 ab->qmi.target_mem[0].size == 7077888 ab->qmi.target_mem[1].size == 8454144 Then allocation failed like before and ath12k_qmi_free_target_mem_chunk() is called to free all allocated segments. Note the first segment is skipped because its v.addr is cleared due to allocation failure: chunk->v.addr = dma_alloc_coherent() Also note that this leaks that segment because it has not been freed. While freeing the second segment, a size of 8454144 is passed to dma_free_coherent(). However remember that this segment is allocated at the first time firmware is loaded, before suspend. So its real size is 524288, much smaller than 8454144. As a result kernel found we are freeing some memory which is in use and thus cras ---truncated--- Weakness: CWE-763 (Release of Invalid Pointer or Reference), CWE-401 (Missing Release of Memory after Effective Lifetime) ## Which versions are affected by CVE-2024-40979? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2024-40979? Apply the vendor's patch. ## Is CVE-2024-40979 being exploited? There is no known exploitation of CVE-2024-40979 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-2024-40979 and fix it if it is affected. What it is: CVE-2024-40979 is a high-severity vulnerability in Linux kernel, published on 12 Jul 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-2024-40979 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-2024-40979/ (Markdown: https://insights.sbomify.com/CVE-2024-40979/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2024-40979 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-40979 - OSV: https://osv.dev/vulnerability/CVE-2024-40979 --- From sbomify Insights: https://insights.sbomify.com/CVE-2024-40979/ Summaries are generated and may contain mistakes; the official description above is the record.