Description
In 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
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
Published:
2026-08-15
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
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References
History
Sat, 15 Aug 2026 06:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In 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 | |
| Title | wifi: ath11k: cancel SSR work items during PCI shutdown | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-08-15T05:59:16.044Z
Reserved: 2026-08-15T05:44:03.892Z
Link: CVE-2026-74407
No data.
Status : Received
Published: 2026-08-15T06:22:42.737
Modified: 2026-08-15T06:22:42.737
Link: CVE-2026-74407
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.