{"cve":"CVE-2026-99130","nvd":{"published":"2026-10-28T11:17:32.800","modified":"2026-10-28T11:17:32.800","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/cancel: don't spin on local work the task can't run\n\nio_uring_cancel_generic() refuses to sleep while any ring on the exiting\ntask's tctx has local work pending. It assumes the task is that ring's\nsubmitter and that the next io_uring_try_cancel_requests() pass will run\nthe work. This does not hold for a ring that was still\nIORING_SETUP_R_DISABLED when the task got its tctx node from\nio_uring_create() or io_ringfd_register(). The submitter is set later by\nIORING_REGISTER_ENABLE_RINGS, possibly from another task, and only the\nsubmitter may run local work on an IORING_SETUP_DEFER_TASKRUN ring. To\nthe exiting task the work stays pending forever, the loop never reaches\nschedule(), and the task trips the WARN_ON_ONCE() once and then spins in\ndo_exit().\n\nAn unprivileged user can set this up at will by creating a disabled\nring, having a child enable it and stop, posting to the ring with\nIORING_OP_MSG_RING and exiting with a request in flight that only the\nchild can complete. The exiting thread burns a CPU until the child runs\nor dies, and with panic_on_warn set the WARN panics the kernel.\n\nFix by skipping the sleep only when io_allowed_defer_tw_run() allows the\ntask to run the work. This is reasonable since work it cannot run cannot\ncomplete any of its requests either, so nothing is lost by sleeping.\nDrop the WARN_ON_ONCE() since handing a disabled ring to another thread\nis a supported scenario, not a bug state.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/3005459e0ddfcef0f555b6e81f672f2c49a1c0aa","https://git.kernel.org/stable/c/94d13387b96e50a4288f7bbdfe401189246a11a1","https://git.kernel.org/stable/c/fddcf4c5321b3ea5f72166c3fd36a9d1c34f80c7"],"products":[],"source":"nvd","synced_at":"2026-10-28T11:37:51.394563875+00:00"},"epss":null,"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}