CVE-2026-81010

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

io_uring/waitid: honor task_work cancellation

io_waitid_cb() may run through the fallback task_work path when

task_work_add() can no longer queue work to the originating task. The

fallback runs from a kworker and io_uring marks such task work as

canceled through tw.cancel.

io_waitid_cb() currently ignores tw.cancel and calls __do_wait().

waitid is task-context dependent: __do_wait() performs child lookup

relative to current, and the retry path also uses

current->signal->wait_chldexit. If the callback runs from the fallback

kworker, current is therefore not the task that submitted the request.

Honor tw.cancel before entering __do_wait(). Complete the request with

-ECANCELED and skip the siginfo copy, since canceled task work may run

without the submitting task's userspace execution context.

Keep the existing siginfo handling for normal waitid completion and

explicit cancellation.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References