GHSA-R6WH-WCH9-FXJR
Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-17 06:33In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: cancel SSR work items during PCI shutdown
A reboot can crash the kernel if it overlaps with WLAN firmware crash recovery (SSR). The crash is a NULL pointer dereference in the MHI teardown path while freeing DMA-backed MHI contexts.
Simplified trace: dma_free_attrs mhi_deinit_dev_ctxt [mhi] ath11k_pci_power_down [ath11k_pci] ath11k_pci_shutdown [ath11k_pci] device_shutdown kernel_restart
On the host side, SSR is driven by the MHI RDDM callback, which queues reset_work to perform device recovery. reset_work power-cycles the device by calling ath11k_hif_power_down() followed by ath11k_hif_power_up(). The power-down phase deinitializes MHI and frees DMA resources.
Shutdown/reboot runs fully asynchronously with this RDDM-driven SSR recovery flow. As a result, the shutdown path (ath11k_pci_shutdown() -> ath11k_pci_power_down()) can race with the SSR recovery sequence.
Fix this by canceling SSR-related work items during PCI shutdown, marking the device as unregistering, and serializing the RDDM callback path that checks and queues reset_work. This ensures that no new SSR recovery work can be queued once teardown has started, and that any in-flight recovery work is fully synchronized before device power-down, preventing MHI teardown and DMA resource freeing from running more than once.
Note: This issue only affects PCI/MHI-based devices. AHB-based ath11k devices do not queue reset_work in normal SSR flows.
Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-04866.5-QCAHSPSWPL_V1_V2_SILICONZ_IOE-1
{
"affected": [],
"aliases": [
"CVE-2026-74407"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-15T06:22:42Z",
"severity": "HIGH"
},
"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() -\u003e 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",
"id": "GHSA-r6wh-wch9-fxjr",
"modified": "2026-08-17T06:33:43Z",
"published": "2026-08-15T06:32:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74407"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/53dd29e8aeb2a1b5f079178551836b85fc6b53df"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8c79aac429b583301f387374ff37c59be671df87"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
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Nomenclature
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.