CVE-2026-99265

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

io uring/openclose: keep the lock in io pipe fixed()

io pipe fixed() installs both ends of the pipe in the fixed file table, drops ->uring lock, and copies the slot numbers to the application. If that faults, it takes the lock again and removes whatever is in these slots.

If the request is run by io-wq the lock really is dropped in between, and the slots are visible to everybody else. By the time the error path gets to them, they may have been closed and reused, by IORING OP CLOSE and a direct open or accept, or by IORING REGISTER FILES UPDATE. Then a file is removed from the table that has nothing to do with the failed request.

Do the copy with the lock held. Faulting in user memory under ->uring lock is fine, the registration paths do it all the time.