{"id":"CVE-2025-21655","summary":"io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/eventfd: ensure io_eventfd_signal() defers another RCU period\n\nio_eventfd_do_signal() is invoked from an RCU callback, but when\ndropping the reference to the io_ev_fd, it calls io_eventfd_free()\ndirectly if the refcount drops to zero. This isn't correct, as any\npotential freeing of the io_ev_fd should be deferred another RCU grace\nperiod.\n\nJust call io_eventfd_put() rather than open-code the dec-and-test and\nfree, which will correctly defer it another RCU grace period.","modified":"2026-05-07T04:17:43.973752Z","published":"2025-01-20T13:48:40.544Z","related":["ALSA-2025:20095","SUSE-SU-2025:0428-1","SUSE-SU-2025:0499-1","SUSE-SU-2025:0557-1","SUSE-SU-2025:0564-1","SUSE-SU-2025:20165-1","SUSE-SU-2025:20166-1","SUSE-SU-2025:20248-1","SUSE-SU-2025:20249-1","USN-7379-2","USN-7380-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21655.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/6b63308c28987c6010b1180c72a6db4df6c68033"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8efff2aa2d95dc437ab67c5b4a9f1d3f367baa10"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a7085c3ae43b86d4b3d1b8275e6a67f14257e3b7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c9a40292a44e78f71258b8522655bffaf5753bdb"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html"},{"type":"WEB","url":"https://project-zero.issues.chromium.org/issues/388499293"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21655.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-21655"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"21a091b970cdbcf3e8ff829234b51be6f9192766"},{"fixed":"6b63308c28987c6010b1180c72a6db4df6c68033"},{"fixed":"8efff2aa2d95dc437ab67c5b4a9f1d3f367baa10"},{"fixed":"a7085c3ae43b86d4b3d1b8275e6a67f14257e3b7"},{"fixed":"c9a40292a44e78f71258b8522655bffaf5753bdb"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21655.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.1.125"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.72"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21655.json"}}],"schema_version":"1.7.5"}