io_uring/waitid: always prune wait queue entry in io_waitid_wait()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: io_uring/waitid: always prune wait queue entry in io_waitid_wait() For a successful return, always remove our entry from the wait queue entry list. Previously this was skipped if a cancelation was in progress, but this can race with another invocation of the wait queue entry callback.

References

• https://git.kernel.org/stable/c/696ba6032081e617564a8113a001b8d7943cb928
• https://git.kernel.org/stable/c/3e2205db2f0608898d535da1964e1b376aacfdaa
• https://git.kernel.org/stable/c/2f8229d53d984c6a05b71ac9e9583d4354e3b91f