{"id":"CVE-2026-64583","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-64583","summary":"usb: gadget: udc: bdc: free IRQ and drain func_wake_notify before teardown","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: udc: bdc: free IRQ and drain func_wake_notify before teardown\n\nThe Broadcom BDC UDC driver registers its IRQ handler with\ndevm_request_irq() in bdc_udc_init(), so the IRQ is released by devm\nonly after bdc_remove() returns.  devm releases resources in reverse\nLIFO order, but bdc_remove() runs bdc_udc_exit() and bdc_hw_exit() ->\nbdc_mem_free() manually before returning: bdc_udc_exit() tears down\nindividual endpoint objects via bdc_free_ep(), while bdc_hw_exit() ->\nbdc_mem_free() frees and NULLs the DMA-coherent status-report ring\n(bdc->srr.sr_bds) and kfree()s bdc->bdc_ep_array.  Both happen while\nthe IRQ handler (bdc_udc_interrupt, requested with IRQF_SHARED)\nremains deliverable in the window up to the post-remove devm\nfree_irq().\n\nOn receipt of a shared interrupt in that window, bdc_udc_interrupt()\ndereferences bdc->srr.sr_bds[bdc->srr.dqp_index] (NULL or freed DMA)\nand dispatches sr_handler callbacks that index into bdc_ep_array,\ncausing a NULL-deref or use-after-free.\n\nThe same window affects the delayed_work bdc->func_wake_notify, which is\narmed from the IRQ handler via bdc_sr_uspc() -> handle_link_state_change()\n-> schedule_delayed_work() and may self-rearm from its own callback\nbdc_func_wake_timer().  No cancel exists anywhere in the driver, so a\nqueued work item that fires after bdc_remove() returns and the bdc\nstructure is devm-freed dereferences freed memory.\n\nReplace devm_request_irq() with request_irq() and add an explicit\nfree_irq(bdc->irq, bdc) in bdc_remove().  Clear BDC_GIE before\nfree_irq() to stop the device from asserting interrupts, then\nfree_irq() drains any in-flight handler, then cancel_delayed_work_sync()\ndrains the func_wake_notify delayed work.  This ordering ensures the\nIRQ handler and delayed work cannot interfere with the subsequent\nendpoint and DMA teardown in bdc_udc_exit() and bdc_hw_exit().  Wire the\nmatching free_irq() into the bdc_udc_init() error path so the IRQ is\nreleased on probe failure, and route the bdc_init_ep() failure through\nerr0 instead of returning directly.\n\nThis issue was found by an in-house static analysis tool.","published":"2026-08-06T07:06:25.335Z","modified":"2026-08-09T03:47:26.054307245Z","cvss":{"score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.6.148"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0583f2fbf8f86ae3a0ce054f96783dd83e65d9bb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1a1d7158420df6b8fa1efc0cdd6ab704801a4fc8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d4964a74717107697999f48bcb4e80a9c0679a27"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dcf3e2f164435b5844706cb8eefef29ebee0eedb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f6fc21ec7ccd83726ba766d73d0b8cc03e726475"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64583.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64583"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-09T03:47:26.054307245Z"}}