CVE-2026-99263
io_uring/poll: avoid retry wakeup loss when dropping ownership
In the Linux kernel, the following vulnerability has been resolved: io_uring/poll: avoid retry wakeup loss when dropping ownership If a wakeup sets IO_POLL_RETRY_FLAG between the owning task consuming the existing instance of IO_POLL_RETRY_FLAG and the loop check of io_poll_check_events(), then we stall on processing the request until an unrelated wakeup comes along. Using atomic_cmpxchg instead of atomic_sub_return to guarantee both the count v and poll_refs are 0 and no wake-ups are missed.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| Linux Linux |
≥ a26a35e9019fd70bf3cf647dcfdae87abc7bacea; < d1f6850086ac6f8b0fa44fb19aa2a468c73ee071 (affected, git) ≥ a26a35e9019fd70bf3cf647dcfdae87abc7bacea; < 41fae2e9e1fa3bee86aee0a25ba90e59ce5024bf (affected, git) ≥ a26a35e9019fd70bf3cf647dcfdae87abc7bacea; < 4ef685b8505615729d75c875f52822238bf76ca6 (affected, git) ≥ a26a35e9019fd70bf3cf647dcfdae87abc7bacea; < afa407c02f3aa0fd872f86c9bf1b34502e0fa8f0 (affected, git) ≥ a26a35e9019fd70bf3cf647dcfdae87abc7bacea; < eb2a50d8235e4580fea9aa20f3fbe1a002c38cb1 (affected, git) ≥ a26a35e9019fd70bf3cf647dcfdae87abc7bacea; < 521e8a65e9b45532295ba1082ef12be6e80c173b (affected, git) 4b702b7d11ce1b9d26fc6d7c5a7ef4ac1d455048 (affected, git) bc4e6ee16778149811333a969a7a893d4cc110c5 (affected, git) ≥ 5.15.82; < 5.16 (affected, semver) ≥ 6.0.11; < 6.1 (affected, semver) Other versions: unaffected |
CNA: Linux |
| Linux Linux |
6.1 (affected) ≥ 0; < 6.1 (unaffected, semver) ≥ 6.1.191; ≤ 6.1.* (unaffected, semver) ≥ 6.6.161; ≤ 6.6.* (unaffected, semver) ≥ 6.12.115; ≤ 6.12.* (unaffected, semver) ≥ 6.18.60; ≤ 6.18.* (unaffected, semver) ≥ 7.2.14; ≤ 7.2.* (unaffected, semver) ≥ 7.3.1; ≤ 7.3.* (unaffected, semver) Other versions: affected |
CNA: Linux |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
No CVSS assessment reported. An unscored record is not a low-severity determination.
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://git.kernel.org/stable/c/d1f6850086ac6f8b0fa44fb19aa2a468c73ee071CNA: Linux
- https://git.kernel.org/stable/c/41fae2e9e1fa3bee86aee0a25ba90e59ce5024bfCNA: Linux
- https://git.kernel.org/stable/c/4ef685b8505615729d75c875f52822238bf76ca6CNA: Linux
- https://git.kernel.org/stable/c/afa407c02f3aa0fd872f86c9bf1b34502e0fa8f0CNA: Linux
- https://git.kernel.org/stable/c/eb2a50d8235e4580fea9aa20f3fbe1a002c38cb1CNA: Linux
- https://git.kernel.org/stable/c/521e8a65e9b45532295ba1082ef12be6e80c173bCNA: Linux
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