CVE-2026-52933

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

io_uring/poll: fix signed comparison in io_poll_get_ownership()

io_poll_get_ownership() uses a signed comparison to check whether

poll_refs has reached the threshold for the slowpath:

if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS))

atomic_read() returns int (signed). When IO_POLL_CANCEL_FLAG

(BIT(31)) is set in poll_refs, the value becomes negative in

signed arithmetic, so the >= 128 comparison always evaluates to

false and the slowpath is never taken.

Fix this by casting the atomic_read() result to unsigned int

before the comparison, so that the cancel flag is treated as a

large positive value and correctly triggers the slowpath.