DEBIAN-CVE-2026-99263: Debian/linux vulnerability
In the Linux kernel, the following vulnerability has been resolved: iouring/poll: avoid retry wakeup loss when dropping ownership If a wakeup sets IOPOLLRETRYFLAG between the owning task consuming the existing instance of IOPOLLRETRYFLAG and the loop check of iopollcheckevents(), then we stall on processing the request until an unrelated wakeup comes along. Using atomiccmpxchg instead of atomicsubreturn to guarantee both the count v and pollrefs are 0 and no wake-ups are missed.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.12.115-1 - Compensating control
In io_uring poll handling, replace atomic_sub_return with atomic_cmpxchg to guarantee that both the count v and poll_refs are 0 and prevent missed wake-ups when dropping ownership.