ghsa-c9qp-46j7-6qfj
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
crypto: qat - flush misc workqueue during device shutdown
Repeated loading and unloading of a device specific QAT driver, for example qat_4xxx, in a tight loop can lead to a crash due to a use-after-free scenario. This occurs when a power management (PM) interrupt triggers just before the device-specific driver (e.g., qat_4xxx.ko) is unloaded, while the core driver (intel_qat.ko) remains loaded.
Since the driver uses a shared workqueue (qat_misc_wq) across all
devices and owned by intel_qat.ko, a deferred routine from the
device-specific driver may still be pending in the queue. If this
routine executes after the driver is unloaded, it can dereference freed
memory, resulting in a page fault and kernel crash like the following:
BUG: unable to handle page fault for address: ffa000002e50a01c
#PF: supervisor read access in kernel mode
RIP: 0010:pm_bh_handler+0x1d2/0x250 [intel_qat]
Call Trace:
pm_bh_handler+0x1d2/0x250 [intel_qat]
process_one_work+0x171/0x340
worker_thread+0x277/0x3a0
kthread+0xf0/0x120
ret_from_fork+0x2d/0x50
To prevent this, flush the misc workqueue during device shutdown to ensure that all pending work items are completed before the driver is unloaded.
Note: This approach may slightly increase shutdown latency if the workqueue contains jobs from other devices, but it ensures correctness and stability.
{
"affected": [],
"aliases": [
"CVE-2025-39721"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-05T18:15:49Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: qat - flush misc workqueue during device shutdown\n\nRepeated loading and unloading of a device specific QAT driver, for\nexample qat_4xxx, in a tight loop can lead to a crash due to a\nuse-after-free scenario. This occurs when a power management (PM)\ninterrupt triggers just before the device-specific driver (e.g.,\nqat_4xxx.ko) is unloaded, while the core driver (intel_qat.ko) remains\nloaded.\n\nSince the driver uses a shared workqueue (`qat_misc_wq`) across all\ndevices and owned by intel_qat.ko, a deferred routine from the\ndevice-specific driver may still be pending in the queue. If this\nroutine executes after the driver is unloaded, it can dereference freed\nmemory, resulting in a page fault and kernel crash like the following:\n\n BUG: unable to handle page fault for address: ffa000002e50a01c\n #PF: supervisor read access in kernel mode\n RIP: 0010:pm_bh_handler+0x1d2/0x250 [intel_qat]\n Call Trace:\n pm_bh_handler+0x1d2/0x250 [intel_qat]\n process_one_work+0x171/0x340\n worker_thread+0x277/0x3a0\n kthread+0xf0/0x120\n ret_from_fork+0x2d/0x50\n\nTo prevent this, flush the misc workqueue during device shutdown to\nensure that all pending work items are completed before the driver is\nunloaded.\n\nNote: This approach may slightly increase shutdown latency if the\nworkqueue contains jobs from other devices, but it ensures correctness\nand stability.",
"id": "GHSA-c9qp-46j7-6qfj",
"modified": "2025-09-05T18:31:27Z",
"published": "2025-09-05T18:31:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39721"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3d4df408ba9bad2b205c7fb8afc1836a6a4ca88a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5858448a6c65d8ee3f8600570d3ce19febcb33be"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e59a52e429e13df3feb34f4853a8e36d121ed937"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fe546f5c50fc474daca6bee72caa7ab68a74c33d"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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