CVE-2025-21655
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.
Scoring
- Severity
- HIGH
- CVSS base score
- 7.8
- CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS probability
- 0.25%
- Published
- 2025-01-20
- Last modified
- 2026-09-08
Affected products
- Linux Linux
- Linux Linux
- Linux Linux
- Linux Linux
- Linux Linux
- Linux Linux
- Linux Linux