CVE-2024-40979

MEDIUM
Published Jul 12, 2024 Modified Sep 17, 2025 CWE-401 CWE-763

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---

Is your site exposed to CVE-2024-40979?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.5
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-401 CWE-401
CWE-763 CWE-763

Affected Products

Vendor Product
linux linux_kernel

References

Frequently Asked Questions

What is CVE-2024-40979? +
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--- It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2024-40979? +
CVE-2024-40979 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2024-40979? +
CVE-2024-40979 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2024-40979? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2024-40979 — free, no signup required.