{"id":69586,"date":"2025-09-05T23:32:23","date_gmt":"2025-09-05T20:02:23","guid":{"rendered":"https:\/\/afaghhosting.net\/blog\/cve-2025-39721-crypto-qat-flush-misc-workqueue-during-device-shutdown\/"},"modified":"2025-09-05T23:32:23","modified_gmt":"2025-09-05T20:02:23","slug":"cve-2025-39721-crypto-qat-flush-misc-workqueue-during-device-shutdown","status":"publish","type":"post","link":"https:\/\/afaghhosting.net\/blog\/cve-2025-39721-crypto-qat-flush-misc-workqueue-during-device-shutdown\/","title":{"rendered":"CVE-2025-39721 &#8211; crypto: qat &#8211; flush misc workqueue during device shutdown"},"content":{"rendered":"<p><strong>CVE ID : <\/strong>CVE-2025-39721<br \/>\n<br \/>\n<strong>Published : <\/strong> Sept. 5, 2025, 6:15 p.m. | 1\u00a0hour ago<br \/>\n<br \/>\n<strong>Description : <\/strong>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>crypto: qat &#8211; flush misc workqueue during device shutdown<\/p>\n<p>Repeated loading and unloading of a device specific QAT driver, for<br \/>\nexample qat_4xxx, in a tight loop can lead to a crash due to a<br \/>\nuse-after-free scenario. This occurs when a power management (PM)<br \/>\ninterrupt triggers just before the device-specific driver (e.g.,<br \/>\nqat_4xxx.ko) is unloaded, while the core driver (intel_qat.ko) remains<br \/>\nloaded.<\/p>\n<p>Since the driver uses a shared workqueue (`qat_misc_wq`) across all<br \/>\ndevices and owned by intel_qat.ko, a deferred routine from the<br \/>\ndevice-specific driver may still be pending in the queue. If this<br \/>\nroutine executes after the driver is unloaded, it can dereference freed<br \/>\nmemory, resulting in a page fault and kernel crash like the following:<\/p>\n<p>    BUG: unable to handle page fault for address: ffa000002e50a01c<br \/>\n    #PF: supervisor read access in kernel mode<br \/>\n    RIP: 0010:pm_bh_handler+0x1d2\/0x250 [intel_qat]\n    Call Trace:<br \/>\n      pm_bh_handler+0x1d2\/0x250 [intel_qat]\n      process_one_work+0x171\/0x340<br \/>\n      worker_thread+0x277\/0x3a0<br \/>\n      kthread+0xf0\/0x120<br \/>\n      ret_from_fork+0x2d\/0x50<\/p>\n<p>To prevent this, flush the misc workqueue during device shutdown to<br \/>\nensure that all pending work items are completed before the driver is<br \/>\nunloaded.<\/p>\n<p>Note: This approach may slightly increase shutdown latency if the<br \/>\nworkqueue contains jobs from other devices, but it ensures correctness<br \/>\nand stability.<br \/>\n<br \/>\n<strong>Severity:<\/strong> 0.0 | NA<br \/>\n<br \/>\nVisit the link for more details, such as CVSS details, affected products, timeline, and more&#8230;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>CVE ID : CVE-2025-39721 Published : Sept. 5, 2025, 6:15 p.m. | 1\u00a0hour ago Description : In the Linux kernel, the following vulnerability has been resolved: crypto: qat &#8211; 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 &hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-69586","post","type-post","status-publish","format-standard","hentry","category-vulnerability"],"_links":{"self":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/69586","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/comments?post=69586"}],"version-history":[{"count":0,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/69586\/revisions"}],"wp:attachment":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/media?parent=69586"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/categories?post=69586"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/tags?post=69586"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}