{"id":"CVE-2024-40979","summary":"wifi: ath12k: fix kernel crash during resume","details":"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-\u003eqmi.mem_seg_count == 2\n\tab-\u003eqmi.target_mem[0].size == 7077888\n\tab-\u003eqmi.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-\u003ev.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---","modified":"2026-05-07T04:17:44.220995Z","published":"2024-07-12T12:32:14.902Z","related":["SUSE-SU-2024:2802-1","SUSE-SU-2024:2896-1","SUSE-SU-2024:2973-1","SUSE-SU-2025:20008-1","SUSE-SU-2025:20028-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/40xxx/CVE-2024-40979.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/303c017821d88ebad887814114d4e5966d320b28"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bb50a4e711ff95348ad53641acb1306d89eb4c3a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/40xxx/CVE-2024-40979.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-40979"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"d889913205cf7ebda905b1e62c5867ed4e39f6c2"},{"fixed":"bb50a4e711ff95348ad53641acb1306d89eb4c3a"},{"fixed":"303c017821d88ebad887814114d4e5966d320b28"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2024-40979.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.3.0"},{"fixed":"6.9.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2024-40979.json"}}],"schema_version":"1.7.5"}