{"id":"CVE-2024-40979","url":"https://www.cyber-defence.io/tools/cve/CVE-2024-40979","generatedAt":"2026-10-28T01:50:08.639Z","title":"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…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: ath12k: fix kernel crash during resume\n\nCurrently during resume, QMI target memory is not properly handled, resulting\nin kernel crash in case DMA remap is not supported:\n\nBUG: Bad page state in process kworker/u16:54  pfn:36e80\npage: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x36e80\npage dumped because: nonzero _refcount\nCall Trace:\n bad_page\n free_page_is_bad_report\n __free_pages_ok\n __free_pages\n dma_direct_free\n dma_free_attrs\n ath12k_qmi_free_target_mem_chunk\n ath12k_qmi_msg_mem_request_cb\n\nThe reason is:\nOnce ath12k module is loaded, firmware sends memory request to host. In case\nDMA remap not supported, ath12k refuses the first request due to failure in\nallocating with large segment size:\n\nath12k_pci 0000:04:00.0: qmi firmware request memory request\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 7077888\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 8454144\nath12k_pci 0000:04:00.0: qmi dma allocation failed (7077888 B type 1), will try later with small size\nath12k_pci 0000:04:00.0: qmi delays mem_request 2\nath12k_pci 0000:04:00.0: qmi firmware request memory request\n\nLater firmware comes back with more but small segments and allocation\nsucceeds:\n\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 262144\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 524288\nath12k_pci 0000:04:00.0: qmi mem seg type 4 size 65536\nath12k_pci 0000:04:00.0: qmi mem seg type 1 size 524288\n\nNow ath12k is working. If suspend is triggered, firmware will be reloaded\nduring resume. As same as before, firmware requests two large segments at\nfirst. In ath12k_qmi_msg_mem_request_cb() segment count and size are\nassigned:\n\n\tab->qmi.mem_seg_count == 2\n\tab->qmi.target_mem[0].size == 7077888\n\tab->qmi.target_mem[1].size == 8454144\n\nThen allocation failed like before and ath12k_qmi_free_target_mem_chunk()\nis called to free all allocated segments. Note the first segment is skipped\nbecause its v.addr is cleared due to allocation failure:\n\n\tchunk->v.addr = dma_alloc_coherent()\n\nAlso note that this leaks that segment because it has not been freed.\n\nWhile freeing the second segment, a size of 8454144 is passed to\ndma_free_coherent(). However remember that this segment is allocated at\nthe first time firmware is loaded, before suspend. So its real size is\n524288, much smaller than 8454144. As a result kernel found we are freeing\nsome memory which is in use and thus cras\n---truncated---","published":"2024-07-12T13:15:19.000Z","lastModified":"2026-10-03T11:17:30.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-401","CWE-763"],"affected":["linux/linux kernel"],"epss":{"score":0.00302,"percentile":0.22756,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.30%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/303c017821d88ebad887814114d4e5966d320b28","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7e323cb55705398123ae087d4870c44e0424e7c0","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bb50a4e711ff95348ad53641acb1306d89eb4c3a","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/303c017821d88ebad887814114d4e5966d320b28","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/bb50a4e711ff95348ad53641acb1306d89eb4c3a","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2024-40979","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}