{"id":"CVE-2026-74407","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-74407","summary":"wifi: ath11k: cancel SSR work items during PCI shutdown","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: ath11k: cancel SSR work items during PCI shutdown\n\nA reboot can crash the kernel if it overlaps with WLAN firmware crash\nrecovery (SSR). The crash is a NULL pointer dereference in the MHI teardown\npath while freeing DMA-backed MHI contexts.\n\nSimplified trace:\n  dma_free_attrs\n  mhi_deinit_dev_ctxt [mhi]\n  ath11k_pci_power_down [ath11k_pci]\n  ath11k_pci_shutdown [ath11k_pci]\n  device_shutdown\n  kernel_restart\n\nOn the host side, SSR is driven by the MHI RDDM callback, which queues\nreset_work to perform device recovery. reset_work power-cycles the device\nby calling ath11k_hif_power_down() followed by ath11k_hif_power_up(). The\npower-down phase deinitializes MHI and frees DMA resources.\n\nShutdown/reboot runs fully asynchronously with this RDDM-driven SSR\nrecovery flow. As a result, the shutdown path\n(ath11k_pci_shutdown() -> ath11k_pci_power_down()) can race with the SSR\nrecovery sequence.\n\nFix this by canceling SSR-related work items during PCI shutdown, marking\nthe device as unregistering, and serializing the RDDM callback path that\nchecks and queues reset_work. This ensures that no new SSR recovery work\ncan be queued once teardown has started, and that any in-flight recovery\nwork is fully synchronized before device power-down, preventing MHI\nteardown and DMA resource freeing from running more than once.\n\nNote: This issue only affects PCI/MHI-based devices. AHB-based ath11k\ndevices do not queue reset_work in normal SSR flows.\n\nTested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-04866.5-QCAHSPSWPL_V1_V2_SILICONZ_IOE-1","published":"2026-08-15T05:59:16.044Z","modified":"2026-08-18T03:56:57.589712739Z","cvss":{"score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"7.1.5"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/53dd29e8aeb2a1b5f079178551836b85fc6b53df"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8c79aac429b583301f387374ff37c59be671df87"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74407.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74407"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-18T03:56:57.589712739Z"}}