CVE-2025-21655 (GCVE-0-2025-21655)
Vulnerability from cvelistv5
Published
2025-01-20 13:48
Modified
2026-10-15 01:02
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period io_eventfd_do_signal() is invoked from an RCU callback, but when dropping the reference to the io_ev_fd, it calls io_eventfd_free() directly if the refcount drops to zero. This isn't correct, as any potential freeing of the io_ev_fd should be deferred another RCU grace period. Just call io_eventfd_put() rather than open-code the dec-and-test and free, which will correctly defer it another RCU grace period.
References
Impacted products
Vendor Product Version
Linux Linux Version: 21a091b970cdbcf3e8ff829234b51be6f9192766
Version: 21a091b970cdbcf3e8ff829234b51be6f9192766
Version: 21a091b970cdbcf3e8ff829234b51be6f9192766
Version: 21a091b970cdbcf3e8ff829234b51be6f9192766
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