CVE-2025-21655 (GCVE-0-2025-21655)

Vulnerability from cvelistv5 – Published: 2025-01-20 13:48 – Updated: 2025-11-03 20:58
VLAI?
Title
io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period
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.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 21a091b970cdbcf3e8ff829234b51be6f9192766 , < 6b63308c28987c6010b1180c72a6db4df6c68033 (git)
Affected: 21a091b970cdbcf3e8ff829234b51be6f9192766 , < 8efff2aa2d95dc437ab67c5b4a9f1d3f367baa10 (git)
Affected: 21a091b970cdbcf3e8ff829234b51be6f9192766 , < a7085c3ae43b86d4b3d1b8275e6a67f14257e3b7 (git)
Affected: 21a091b970cdbcf3e8ff829234b51be6f9192766 , < c9a40292a44e78f71258b8522655bffaf5753bdb (git)
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    Linux Linux Affected: 6.1
Unaffected: 0 , < 6.1 (semver)
Unaffected: 6.1.125 , ≤ 6.1.* (semver)
Unaffected: 6.6.72 , ≤ 6.6.* (semver)
Unaffected: 6.12.10 , ≤ 6.12.* (semver)
Unaffected: 6.13 , ≤ * (original_commit_for_fix)
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